Biology

Ch-1 The Cell

I. Introduction to the Cell

Definition: The structural and functional unit of all living organisms, capable of performing all essential life processes independently.
Discovery of the Cell and Cell Theory:
- Robert Hooke (1665): First observed cells (in cork).
- Anton van Leeuwenhoek: Observed microorganisms and living cells.
- Matthias Schleiden (1838) and Theodor Schwann (1839): All plants and animals are made of cells (Cell Theory components).
- Rudolf Virchow (1855): "Omnis cellula e cellula" (Every cell originates from a pre-existing cell) (Added to Cell Theory).
Types of Cells:

Feature	Prokaryotic Cell	Eukaryotic Cell
Nucleus	Absent (genetic material in nucleoid region)	Present (membrane-bound)
Membrane-bound Organelles	Absent	Present (e.g., mitochondria, ER, Golgi, lysosomes, plastids)
Genetic Material	Single, circular DNA (naked)	Multiple, linear DNA (associated with histones in chromosomes)
Ribosomes	70S	Primarily 80S (cytoplasmic); 70S in some organelles
Cell Wall	Usually present (distinct composition, e.g., peptidoglycan)	Composition varies; absent in animal cells, present in plants (cellulose), fungi (chitin)
Cell Division	Binary Fission	Mitosis & Meiosis

II. Cell Structure and Organelles

(i) Cell Membrane (Plasma Membrane):
- Semi-permeable boundary separating cell interior from the external environment.
- Protects the cell and regulates molecule movement.
- Structure (Fluid Mosaic Model):
  1. Phospholipid Bilayer: Main component (hydrophobic and hydrophilic parts).
  2. Proteins: Assist in transport, signaling, support.
  3. Cholesterol: Maintains stability and flexibility.
  4. Glycoproteins and Glycolipids: Role in cell recognition.
- Functions:
  1. Selective Permeability Control.
  2. Cell Signaling.
  3. Molecular Transport (Active & Passive).
  4. Maintaining Cell Shape.
  5. Cell Communication.
- Methods of Transport:
  - Passive Transport (No energy): Diffusion, Osmosis, Facilitated Diffusion.
  - Active Transport (Uses ATP): Protein Pumps, Endocytosis, Exocytosis.
(ii) Cell Wall:
- Rigid, outer covering providing protection, structure, and support.
- Found in plant cells, bacteria, fungi, some protists; absent in animal cells.
- Structure: Varies by organism:
  1. In Plant Cells: Primarily cellulose, hemicellulose, pectin, proteins; lignin in mature cells.
  2. In Fungi: Primarily chitin.
  3. In Bacteria: Contains peptidoglycan.
  4. In Algae: Cellulose, galactans, mannans, calcium carbonate.
- Functions:
  1. Protection (trauma, chemicals, pathogens).
  2. Maintaining Cell Shape.
  3. Prevention of Overhydration (prevents bursting).
  4. Protection from Environmental Stress.
  5. Cell-to-Cell Communication (via plasmodesmata in plants).
- Difference between Cell Membrane and Cell Wall:

Feature	Cell Membrane	Cell Wall
Location	All cells	Plants, bacteria, fungi, protists
Structure	Phospholipids and proteins	Cellulose, chitin, peptidoglycan, etc.

Cell Nucleus:
- Most important part, controls biological functions, stores DNA.
- "Brain" of the cell, directs activities.
- Structure:
  1. Nuclear Membrane: Double membrane with pores.
  2. Nucleoplasm: Fluid inside, suspends components.
  3. Chromosomes: Collections of DNA strands.
  4. Nucleolus: Synthesizes rRNA and produces ribosomes.
- Functions:
  1. Genetic Control (development, growth, division).
  2. Protein Synthesis (via ribosome production in nucleolus).
  3. Cell Division (DNA redistribution).
  4. Growth and Development Control.
  5. Storage and Processing of DNA/RNA.
Cytoplasm:
- Semi-fluid substance between cell membrane and nucleus.
- Aids biological functions and supports organelles.
- Structure:
  1. Cytosol: Gel-like substance (water, salts, proteins, enzymes, etc.).
  2. Cell Organelles: Various membrane-bound structures.
  3. Inclusions: Solid structures (granules, droplets).
- Functions:
  1. Center for Biochemical Reactions (glycolysis, protein synthesis, etc.).
  2. Support to Organelles.
  3. Transport of Substances (cytoplasmic streaming).
  4. Energy Production (via mitochondria).
  5. Aids in Cell Division.
- Types:
  1. Endoplasm: Thick, viscous inner part (higher activity).
  2. Ectoplasm: Outer, lighter, transparent part (shape/support).
- Differences between Plant and Animal Cell Cytoplasm:

Feature	Plant Cell	Animal Cell
Structure	More organized, large vacuoles	Smaller or absent vacuoles
Flow	Slow and limited	More dynamic
Organelles	Plastids present	No plastids

(i) Mitochondria:

* "Powerhouse of the cell," generates energy (ATP). * Membrane-bound organelle. * Structure: 1. Outer Membrane: Smooth, permeable. 2. Inner Membrane: Folded into cristae (increased surface area). 3. Intermembrane Space: Between outer and inner membranes. 4. Matrix: Fluid inside inner membrane (mitochondrial DNA, ribosomes, enzymes). * Functions: 1. Energy Production (ATP Synthesis via aerobic respiration). 2. Cellular Respiration (Krebs Cycle, Electron Transport Chain). 3. Assistance in Cell Division and Growth. 4. Control of Apoptosis (Programmed Cell Death). 5. Maintaining Calcium Homeostasis. * Unique Features: Contains its own DNA and ribosomes (semi-autonomous).

Ribosomes:
- Composed of rRNA and proteins; two subunits.
- Types:
  - Free ribosomes (in cytoplasm): Proteins for intracellular use.
  - Bound ribosomes (on RER): Membrane and secretory proteins.
- Functions:
  1. Protein synthesis (translation).
  2. Enzyme production.
  3. Contribution to cell growth and division.
Golgi Body (Golgi Apparatus, Golgi Complex):
- Structure: Stack of flattened, membrane-bound sacs (cisternae).
  - Cis face (forming face).
  - Trans face (maturing face).
  - Golgi vesicles.
- Functions:
  1. Modification of proteins and lipids (glycosylation, lipid modification).
  2. Packaging and transport of molecules (to membrane, lysosomes, extracellular).
  3. Formation of lysosomes.
  4. Control of secretion (hormones, enzymes).
  5. Formation and repair of new cell membrane.
  6. Synthesis of pectin and cellulose in plant cell walls.
Lysosome:
- Structure: Single membrane-bound organelles containing hydrolytic enzymes (proteases, lipases, etc.), functioning at acidic pH (~5). Originate from the Golgi apparatus.
- Functions:
  1. Digests waste materials (damaged parts, dead cells, unwanted substances).
  2. Autolysis (self-destruction - "suicidal bag").
  3. Participates in endocytosis and phagocytosis (destroying pathogens).
  4. Manages waste and recycling (breaks down old organelles).
  5. Helps in cell division and growth (restructuring).
- Types: Primary, Secondary, Autophagic, Heterophagic.
Endoplasmic Reticulum (ER):
- Membrane-bound structure in eukaryotic cells.
- Role in synthesis, storage, transport.
- Types:
  1. Rough Endoplasmic Reticulum (RER): Has ribosomes, aids protein synthesis/modification (to Golgi/lysosomes).
  2. Smooth Endoplasmic Reticulum (SER): Lacks ribosomes, aids lipid/steroid synthesis, detoxification, Ca2+ storage.
- Functions:
  1. Synthesis of proteins (RER) and lipids/steroids (SER).
  2. Transport of substances within the cell.
  3. Detoxification (SER).
  4. Storage of calcium ions (SER).
- Relationship with Golgi Apparatus: Proteins/lipids from ER are modified and transported by Golgi.
(vi) Chloroplast:

Membrane-bound organelle in plant/algal cells. Responsible for photosynthesis.
Structure:
1. Double Membrane: Outer & inner.
2. Stroma: Fluid space inside (enzymes, DNA, ribosomes, Calvin cycle).
3. Thylakoid: Membranous sacs (grana when stacked); contain chlorophyll.
4. Chlorophyll & Other Pigments: Absorb light.
Functions:
1. Photosynthesis (Light reactions in thylakoid, Calvin Cycle in stroma).
2. Oxygen Production.
3. Amino Acid & Fatty Acid Synthesis.
4. Own DNA and Ribosomes (semi-autonomous).
Importance: Base of food chain, maintains atmospheric oxygen.
(vii) Centriole:
- Microtubular structure in animal cells, some plants/protists. Role in cell division and microtubule organization.
- Structure:
  1. Tubular Structure: Made of microtubules (9+0 structure).
  2. Present in Pairs: Called a centrosome; assists in spindle fiber formation.
- Functions:
  1. Role in Cell Division: Builds spindle fibers to separate chromosomes (mitosis/meiosis).
  2. Microtubule Organization: Maintains cell structure (cytoskeleton), regulates organelle position.
  3. Cilia & Flagella Formation: Forms basal body.
  4. Organizing Golgi Apparatus and Vesicles.
- Importance: Essential for cell division (animal cells), chromosome segregation, genetic stability.

III. Cell Division

Definition: Process by which a parent cell divides into two or more daughter cells; essential for growth, development, repair, reproduction.
Types of Cell Division:
1. Mitosis: Equal division. Parent cell forms two daughter cells with the same chromosome number (diploid, 2n).
  - Aids in general body growth, tissue repair, regeneration.
  - Stages: Interphase (preparation), Prophase (chromosome condense, centrioles move), Metaphase (chromosomes align), Anaphase (chromatids separate), Telophase (new nuclei), Cytokinesis (cytoplasm divides).
  - Where occurs: Somatic cells (skin, bone marrow, meristematic cells).
2. Meiosis: Special division. Parent cell forms four daughter cells with half the chromosome number (haploid, n). Occurs in gamete formation.
  - Stages: Meiosis I (chromosome number halved, crossing over/genetic variation), Meiosis II (similar to mitosis, forms 4 cells).
  - Where occurs: Reproductive cells (ovaries, testes).
3. Amitosis: Simple, direct division. Cell divides into two parts without proper chromosome separation.

Feature	Mitosis	Meiosis
Type of Division	Equational Division (chromosome number remains the same)	Reduction Division (chromosome number is halved)
Number of Divisions	One	Two (Meiosis I and Meiosis II)
DNA Replication	Occurs once before the division (during Interphase)	Occurs once before Meiosis I (during Interphase), but not before Meiosis II
Number of Daughter Cells	Two	Four
Chromosome Number of Daughter Cells	Same as parent cell (e.g., diploid parent -> diploid daughters)	Half of parent cell (e.g., diploid parent -> haploid daughters)
Genetic Composition of Daughter Cells	Genetically identical to parent cell	Genetically varied from parent cell and each other (due to recombination)
Occurrence	Diploid somatic cells (generally), also haploid cells in some exceptions	Diploid cells destined to form gametes (in reproductive organs/structures)
Purpose/Role	Growth, tissue repair, cell replacement, asexual reproduction	Sexual reproduction, production of gametes, introduction of genetic variation
Typical Outcome Cells	Somatic cells, body cells	Gametes (sperm, egg), spores

Importance of Cell Division:
1. Growth (new cells formed).
2. Tissue Repair (damaged cells regenerated).
3. Reproduction (sexual and asexual).
4. Genetic Variation (via meiosis, aids evolution).
5. Replacement of Old Cells.

Ch-2 Control and Coordination

The Nervous System

I. Introduction and Role

Vital system for control and coordination of bodily activities.
Works with the endocrine system for controlled and coordinated body function.
Operates by detecting stimuli (internal/external) and generating a response.
Enables organisms to interact with their environment, regulate internal functions, and coordinate complex behaviors.
Ensures controlled exchange of information between body parts for stability and response to changes.

II. Basic Unit: The Neuron (Nerve Cell)

The functional unit of the nervous system.
Specialized for conducting information via electrical impulses.
Composed of nervous tissue.
Parts of a Neuron:
- Cell Body (Cyton or Soma): Contains nucleus, cytoplasm. Receives impulses from dendrites, transmits to axon. Cytoplasm contains Nissl bodies (rough ER).
- Dendrites: Short, branched extensions. Receive information (impulses) from receptors or other neurons. Information acquired at dendritic tip.
- Axon (Nerve Fibre): Long projection. Carries impulses away from the cell body to other neurons, muscles, or glands. May have an insulating fatty sheath (neurilemma) with gaps (Node of Ranvier). Ends in swollen axon bulbs storing neurotransmitters. Can be up to a metre long.

III. How Information is Transmitted

Nerve Impulse Transmission:
- Neurons are excitable cells due to polarized membranes.
- Stimulation generates an electrical impulse (electrochemical process).
- Impulse travels from dendrite -> cell body -> axon.
- Transmission along axon involves depolarization and repolarization.
Synapse:
- Junction between axon ending of one neuron and dendrite/cell body of another.
- Small gap: synaptic cleft.
- Electrical impulse converted to a chemical signal.
- Neurotransmitters released into cleft, bind to receptors on next cell, generating a new impulse.

IV. Structure of the Nervous System: Divisions

Nerve: Thread-like structure formed by a bundle of axons bound by connective tissue. Emerge from brain/spinal cord.
- Sensory Nerves (Afferent): Carry impulses from receptors (sense organs) to CNS. (e.g., Optic nerve). Contain sensory fibres.
- Motor Nerves (Efferent): Carry impulses from CNS to effector organs (muscles/glands). (e.g., Nerve to eye muscles). Contain motor fibres.
- Mixed Nerves: Contain both sensory and motor fibres. (e.g., Spinal nerve).
Central Nervous System (CNS):
- Consists of the brain and spinal cord.
- The information processing and control center.
- Brain:
  - Main coordinating center, located in skull.
  - Protected by cranium (brain box), three meninges (dura mater, arachnoid, pia mater), and cerebrospinal fluid (CSF).

* Major Parts: * Forebrain: Includes cerebrum (thinking, intelligence, memory, voluntary actions, processing sensory info), thalamus (relay for sensory impulses), and hypothalamus (controls motivated behavior, pituitary, body temperature). * Midbrain: Between forebrain/hindbrain. Receives/integrates visual, tactile, auditory inputs. * Hindbrain: Consists of cerebellum (precision of voluntary actions, posture, balance), pons (interconnects brain regions), and medulla oblongata (controls involuntary actions: heartbeat, breathing, blood pressure, salivation, vomiting; connects to spinal cord). * Spinal Cord: * Extends from medulla oblongata down vertebral column. * Protected by vertebral column, meninges, and CSF. * Controls reflexes below the neck. * Conducts sensory impulses to the brain. * Conducts motor responses from the brain to trunk/limbs. * Forms reflex arcs.

Peripheral Nervous System (PNS):
- Network of nerves connecting the CNS to the rest of the body.
- Facilitates communication between CNS and other parts.
- Divisions:
  - Somatic Nervous System: Relays impulses from CNS to skeletal muscles. Controls voluntary actions. Includes cranial and spinal nerves.
  - Autonomic Nervous System (ANS): Transmits impulses from CNS to involuntary organs and smooth muscles. Controls involuntary actions (heartbeat, digestion, sweating).
    - Sympathetic Nervous System: Prepares body for emergency ("fight or flight"). Accelerates heartbeat, dilates pupils, constricts blood vessels, releases sugar, etc.
    - Parasympathetic Nervous System: Restores normal body conditions after emergency. Slows heartbeat, constricts pupils, etc. Often have opposite but complementary effects.

V. Sensory Input: Sense Organs (Receptors)

Specialized structures that detect information from the environment.
Examples: inner ear (hearing/balance), nose (smell), tongue (taste), eyes (vision), skin (touch, pressure, pain, temperature).
Detect stimulus and trigger nerve impulses that are sent to the CNS for processing.

VI. Reflex Actions

A sudden, involuntary response to a stimulus without conscious thought.
Examples: pulling hand from hot object, blinking, removing foot from nail, pupil constriction, knee jerk.
Controlled by the spinal cord (though impulse info reaches brain).
Reflex Arc (Pathway):
1. Stimulus: External factor (e.g., heat).
2. Receptor: Detects stimulus (e.g., skin nerves).
3. Sensory Neuron: Carries signal to CNS (spinal cord/brainstem).
4. Interneuron (Association Neuron): (Optional) In CNS, processes info.
5. Motor Neuron: Carries response instruction to effector.
6. Effector (Muscle or Gland): Carries out the action.
Types of Reflex Actions:
- Natural (Innate): Automatic, no practice needed (suckling, blinking, sneezing).
- Acquired (Conditioned): Developed through practice/experience (applying brakes, catching a ball).
Importance: Quick response, protection, energy conservation, life-saving.

VII. Overall Functions of the Nervous System

Sensory Function: Receives information from the environment (temperature, light, sound, etc.).
Integrative Function: Analyzes information and makes decisions.
Motor Function: Stimulates effector organs (muscles/glands) to respond.

VIII. Nervous vs. Hormonal Coordination

Nervous System:
- Rapid, point-to-point coordination.
- Uses electrical impulses and chemical signals (neurotransmitters).
- Effects usually localized and short-lived.
Endocrine System:
- Slower coordination.
- Uses hormones transported by blood.
- Effects can be general and long-lasting.
Systems often work together for coordination.

IX. Protection of the Nervous System

Brain: Protected by bony skull (cranium), cushioned by meninges and cerebrospinal fluid (shock absorption).
Spinal Cord: Protected by vertebral column (backbone), covered by meninges and cerebrospinal fluid.

Ch-3 Reproduction in Human Beings

Humans reproduce sexually and are viviparous mammals. It's a complex process involving specific male and female reproductive systems, gamete formation, fertilization, embryonic development, and birth.

Human Reproductive System:

A. Male Reproductive System: Responsible for producing and transferring sperm.
- Testes: Produce sperm and the hormone testosterone.
- Scrotum: Sac holding testes outside the body, maintaining optimal temperature for sperm production.
- Epididymis: Stores and matures sperm.
- Vas Deferens: Tubes that transport sperm from the epididymis.
- Accessory Glands (Prostate Gland, Cowper's Gland, Seminal Vesicles): Produce seminal fluid (semen) that nourishes sperm and aids motility.
- Penis: External organ for transferring sperm into the female reproductive tract.
B. Female Reproductive System: Responsible for producing ova, receiving sperm, fertilization, and embryonic development.
- Ovaries: Produce ova (eggs) and female hormones (estrogen, progesterone).
- Fallopian Tubes (Oviducts): Transport ova from ovaries to the uterus; site of fertilization.
- Uterus: Muscular organ where the fertilized egg implants and the embryo/fetus develops.
- Cervix: Lower, narrow part of the uterus that opens into the vagina.
- Vagina: Muscular tube connecting the cervix to the outside; receives penis during copulation and serves as the birth canal.

Process of Human Reproduction

Gametogenesis: Formation of gametes.
- Spermatogenesis: Sperm formation in the testes (males).
- Oogenesis: Ovum (egg) formation in the ovaries (females).
Fertilization: Fusion of sperm and ovum, usually occurring in the fallopian tube, forming a zygote.
Embryonic Development:
- The zygote undergoes cleavage (cell division) and forms an embryo.
- The embryo travels to the uterus and implants in the uterine wall (implantation).
- Gestation Period: The embryo develops into a fetus inside the uterus over approximately 9 months.
Parturition: The process of childbirth, where the fully developed fetus is expelled from the uterus.

Reproductive Hormones in Humans

Hormone	Source	Function
FSH (Follicle Stimulating)	Pituitary Gland	Stimulates development of ovarian follicles (egg) and sperm production.
LH (Luteinizing)	Pituitary Gland	Triggers ovulation (egg release) in females; stimulates testosterone production in males.
Testosterone	Testes	Primary male sex hormone; sperm production, male sexual development/characteristics.
Estrogen	Ovaries	Primary female sex hormone; female sexual development/characteristics, menstrual cycle, maintains pregnancy.
Progesterone	Ovaries	Prepares and maintains the uterus for pregnancy; inhibits uterine contractions.

Menstrual Cycle:

A cyclical series of changes in the female reproductive system, typically around 28 days, preparing the uterus for potential pregnancy. It has four main phases:

Menstrual Phase (Days 1-5): Shedding of the uterine lining (menstruation).
Follicular Phase (Days 6-14): Follicle development in the ovary, secretion of estrogen, thickening of the uterine lining.
Ovulation Phase (Around Day 14): Release of the mature ovum from the ovary.
Luteal Phase (Days 15-28): Formation of corpus luteum, secretion of progesterone to prepare uterus for implantation. If no pregnancy, corpus luteum degenerates, hormone levels drop, triggering menstruation.

Contraception:

Methods used to prevent unwanted pregnancy.

Natural Methods: Based on understanding the menstrual cycle (safe period) or preventing sperm from entering the vagina (withdrawal).
- Examples: Safe period method, Withdrawal method.
Barrier Methods: Physically prevent sperm from reaching the egg.
- Examples: Condoms (male/female), Diaphragms, Contraceptive caps, Spermicides.
Hormonal Methods: Use hormones to prevent ovulation, thicken cervical mucus, or thin uterine lining.
- Examples: Contraceptive pills, Injections, Implants, Patches.
Permanent Methods: Surgical procedures to permanently prevent gamete transfer.
- Examples: Vasectomy (males - blocks vas deferens), Tubectomy (females - blocks fallopian tubes).

Ch-4: Excretion in Human beings

Excretion is the vital process by which organisms eliminate toxic and unusable waste products generated by metabolic activities from their bodies. Accumulated waste can be harmful, making excretion essential for maintaining internal balance and survival.

The human excretory system is responsible for filtering blood and removing waste products in the form of urine. It primarily consists of the kidneys and associated organs.

A. Main Organs of the Excretory System:

Kidneys:
- There are two kidneys, bean-shaped organs located on either side of the spine, below the ribs.
- They are the principal excretory organs, filtering blood to remove nitrogenous wastes (urea, ammonia, uric acid) and excess salts and water.
- The functional unit of the kidney is the Nephron. Each kidney contains millions of nephrons.
- Functions of Nephrons:
  - Glomerular Filtration: Blood is filtered under pressure, moving water, small solutes, and waste products from the blood into the nephron tubule.
  - Reabsorption: Useful substances (like glucose, amino acids, most water, and essential salts) are selectively reabsorbed from the filtrate back into the blood.
  - Tubular Secretion: Additional waste products, excess ions, and toxic substances are actively transported from the blood into the nephron tubule.
- The remaining fluid in the tubule is urine.
Ureters:
- Two thin, muscular tubes extending from each kidney down to the urinary bladder.
- They transport urine from the renal pelvis of the kidney to the bladder through peristalsis (muscle contractions) and gravity.
Urinary Bladder:
- A hollow, muscular, sac-like organ located in the pelvis.
- It temporarily stores urine received from the ureters.
- Its muscular walls expand as it fills with urine.
- When the bladder is full, it triggers the urge to urinate (micturition).
Urethra:
- A tube that carries urine from the urinary bladder out of the body.
- Its length differs in males and females:
  - In males, the urethra is longer and also serves as a passage for semen during ejaculation (part of both urinary and reproductive systems).
  - In females, the urethra is shorter and serves only for the passage of urine.

B. Accessory Excretory Organs:

Other organs in the body also contribute to waste removal:

Skin:
- Excretes water, salts, and small amounts of urea in the form of sweat.
- Plays a role in thermoregulation (temperature control) through sweating.
Lungs:
- Excrete gaseous waste products, primarily carbon dioxide, which is a major metabolic waste product.
- Also remove water vapor during exhalation.
Liver:
- Not a primary excretory organ in the sense of removing wastes from the body, but crucial for converting toxic substances into less harmful forms that can be excreted.
- Converts highly toxic ammonia (a nitrogenous waste product) into less toxic urea, which is then transported by the blood to the kidneys for excretion.
- Excretes bile pigments, cholesterol, excess hormones, and drugs into bile, which is eliminated with feces (though feces elimination is digestion, not excretion).

**C. Process of Excretion

The process involves the formation of urine in the kidneys through filtration, reabsorption, and secretion, followed by its transport, storage, and elimination.

D. Diseases and Conditions Related to the Excretory System:

Kidney Stones: Hard deposits formed from minerals and salts within the kidney.
Kidney Failure (Renal Failure): A condition where the kidneys lose their ability to filter waste from the blood effectively. This often requires medical intervention like dialysis.
Uremia: A condition where there is an excessive build-up of urea and other nitrogenous waste products in the blood, typically due to kidney dysfunction.
Urinary Tract Infection (UTI): An infection in any part of the urinary system, most commonly caused by bacteria.

E. Dialysis:

An artificial medical process used when the kidneys are unable to perform their function of filtering waste from the blood.
A dialysis machine or procedure temporarily performs the role of the kidneys, removing excess water, solutes, and toxins from the bloodstream.

Ch-5 Respiration in Human Beings

Respiration is a vital biological process where organisms convert chemical energy stored in food (primarily glucose) into usable energy (ATP). This process typically involves the intake of oxygen and the release of waste products like carbon dioxide and water. The energy produced fuels all essential biological functions.

The human respiratory system is responsible for the intake of oxygen and the expulsion of carbon dioxide, enabling cellular respiration to produce energy.

A. Major Organs of the Respiratory System:

Nose: The entry point for air. Contains hairs and mucus to filter, warm, and humidify incoming air. The nasal cavity leads to the pharynx.
Pharynx: A passage connecting the nasal cavity and mouth to the trachea and esophagus. Contains the epiglottis, a flap that prevents food from entering the trachea.
Trachea (Windpipe): A tube (about 10-12 cm long) that carries air from the pharynx to the lungs. Supported by C-shaped rings of cartilage to prevent collapse. Lined with cilia and mucus to trap and move particles.
Bronchi and Bronchioles: The trachea divides into two main bronchi, one entering each lung. The bronchi repeatedly branch into smaller tubes called bronchioles, which eventually lead to the alveoli.
Lungs: The primary organs of respiration, located in the thoracic cavity. The right lung has three lobes, and the left lung has two. They contain millions of tiny air sacs called alveoli.
Alveoli: Microscopic air sacs in the lungs with thin walls, surrounded by capillaries. They are the primary sites of gas exchange (Oxygen diffuses from the alveoli into the blood capillaries, and carbon dioxide diffuses from the blood capillaries into the alveoli).
Diaphragm: A large, dome-shaped muscle located at the base of the chest cavity. It plays a crucial role in controlling breathing movements.

B. Process of Respiration (Breathing Mechanism) in Humans:

Breathing involves two main phases, controlled largely by the diaphragm and intercostal muscles:

Inhalation (Breathing In):
- The diaphragm contracts and flattens, and the intercostal muscles contract, lifting the rib cage upwards and outwards.
- This increases the volume of the thoracic cavity and lungs.
- Air pressure inside the lungs decreases, drawing air from the atmosphere into the nose/mouth, through the pharynx, trachea, bronchi, and bronchioles, reaching the alveoli.
- Air is filtered, warmed, and humidified along the way.
Gas Exchange (at the Alveoli):
- Oxygen concentration is high in the inhaled air within the alveoli, while it's low in the blood arriving from the body. Oxygen diffuses rapidly across the thin alveolar-capillary membrane into the blood.
- Carbon dioxide concentration is high in the blood arriving from the body (a waste product of metabolism), while it's low in the alveolar air. Carbon dioxide diffuses rapidly from the blood into the alveoli.
- Oxygen binds to hemoglobin in red blood cells for transport to body tissues.
Exhalation (Breathing Out):
- The diaphragm relaxes and returns to its dome shape, and the intercostal muscles relax, allowing the rib cage to move downwards and inwards.
- This decreases the volume of the thoracic cavity and lungs.
- Air pressure inside the lungs increases, forcing air (rich in carbon dioxide) out through the same pathway in reverse.

C. Types of Respiration in Humans (Levels of Gas Exchange):

While breathing facilitates gas exchange, the term "respiration" also refers to processes at different levels:

External Respiration: The exchange of gases (O₂ and CO₂) between the air in the lungs (alveoli) and the blood in the pulmonary capillaries.
Internal Respiration: The exchange of gases (O₂ and CO₂) between the blood in systemic capillaries and the body's cells/tissues. Oxygen is released to cells, and carbon dioxide from cellular metabolism enters the blood.
Cellular Respiration: The biochemical process occurring within cells (primarily in mitochondria) where glucose is broken down in the presence of oxygen to produce ATP energy, carbon dioxide, and water. This is the fundamental process that uses the oxygen delivered by external and internal respiration.
- Equation: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + Energy (ATP)

D. Diseases Related to the Respiratory System:

Disease	Cause	Symptoms
Asthma	Chronic inflammation and narrowing of airways	Difficulty breathing, wheezing, chest tightness, coughing
Pneumonia	Infection (bacterial, viral, fungal) of lungs	Fever, cough (often with phlegm), chest pain, difficulty breathing
Bronchitis	Inflammation of the lining of bronchial tubes	Cough (often with mucus), shortness of breath, chest discomfort
Tuberculosis (TB)	Bacterial infection (Mycobacterium tuberculosis)	Prolonged cough, fever, weight loss, fatigue, night sweats
Silicosis	Inhalation of silica dust	Cough, shortness of breath, fatigue (a type of lung disease)
COPD (Chronic Obstructive Pulmonary Disease)	Chronic inflammatory lung diseases (often from smoking)	Persistent cough, phlegm, shortness of breath, wheezing

E. Tips for a Healthy Respiratory System:

Avoid smoking: Smoking is the leading cause of preventable lung disease.
Minimize exposure to pollution: Stay indoors during high pollution days, wear masks in polluted environments.
Regular exercise: Improves lung capacity and efficiency.
Stay hydrated: Keeps airway mucus thin and helps clear irritants.
Balanced diet: Supports overall health, including lung function.
Practice good hygiene: Prevents respiratory infections.

Ch-6 Circulation System in Human beings

Function: Responsible for the continuous transport of essential substances (oxygen, nutrients, hormones) and the removal of waste products (carbon dioxide, metabolic byproducts) throughout the body, vital for maintaining life.
Type: A closed, double circulatory system, meaning blood flows within a network of vessels and passes through the heart twice in one complete circuit.
Main Components:
1. Heart: A muscular pump.
2. Blood: A fluid connective tissue acting as the transport medium.
3. Blood Vessels: A network of tubes (arteries, veins, capillaries) through which blood flows.
Associated Fluid: Lymph, another body fluid, also aids in the transport of certain substances and plays a role in immunity.

A. The Heart

Location & Size: A muscular organ, about the size of a fist, located in the chest cavity (thoracic cavity), slightly tilted towards the left.
Function: Acts as a non-stop pump, propelling blood throughout the body via rhythmic contractions.
Structure:
- Layers of the Heart Wall:
  - Endocardium: Inner smooth lining.
  - Myocardium: Middle, thick muscular layer composed of specialized cardiac muscle fibers responsible for contraction and relaxation without fatigue.
  - Pericardium: Outer protective sac that reduces friction.
- Chambers: Four chambers separated by a muscular wall (septum) which prevents the mixing of oxygenated and deoxygenated blood.

Chamber Name	Location	Function	Wall Thickness Note
Right Atrium (RA)	Upper right	Receives deoxygenated blood from the body (via Vena Cava).	Thin-walled
Right Ventricle (RV)	Lower right	Pumps deoxygenated blood to the lungs (via Pulmonary Artery).	Thicker than atria
Left Atrium (LA)	Upper left	Receives oxygenated blood from the lungs (via Pulmonary Veins).	Thin-walled
Left Ventricle (LV)	Lower left	Pumps oxygenated blood to the entire body (via Aorta).	Thickest walls due to high pressure needed for systemic circulation.

*   **Valves:** Ensure unidirectional blood flow, preventing backflow.

Valve Name	Location	Function	Type
Tricuspid Valve	Between Right Atrium & Right Ventricle	Controls flow from RA to RV.	Atrioventricular
Pulmonary Valve	Between Right Ventricle & Pulmonary Artery	Controls flow from RV to Pulmonary Artery (to lungs).	Semilunar
Mitral (Bicuspid) Valve	Between Left Atrium & Left Ventricle	Controls flow from LA to LV.	Atrioventricular
Aortic Valve	Between Left Ventricle & Aorta	Controls flow from LV to Aorta (to body).	Semilunar

Functioning (Mechanism):
- Electrical Conduction:
  - Sinoatrial Node (SA Node): Located in the right atrium, acts as the heart's natural pacemaker, generating electrical impulses rhythmically (approx. 70-75 per minute).
  - Impulses spread through atria, causing them to contract (atrial systole).
  - Signal reaches the Atrioventricular Node (AV Node), where it's briefly delayed.
  - Signal travels down the Bundle of His and Purkinje fibers in the ventricular walls.
  - This triggers ventricular contraction (ventricular systole).
- Cardiac Cycle: The sequence of events during one heartbeat (contraction/systole and relaxation/diastole). Duration is about 0.8 seconds at a normal heart rate.
- Heartbeat: The rhythmic contraction and relaxation of the heart. Normal resting Heart Rate is 70-80 beats per minute (typically cited as 72 bpm).
- Pulse: The rhythmic throbbing felt in arteries due to the pressure wave from each heartbeat. Pulse rate reflects heart rate.
- Stroke Volume: The volume of blood pumped out by each ventricle per beat (approx. 70 mL).
- Cardiac Output: The total volume of blood pumped out by each ventricle per minute (Stroke Volume x Heart Rate). Averages 5 Litres (5000 mL) per minute in a healthy adult.
- Heart Sounds: "Lubb" (first sound) occurs due to the closure of Atrioventricular (Tricuspid and Mitral) valves at the start of ventricular systole. "Dubb" (second sound) occurs due to the closure of Semilunar (Aortic and Pulmonary) valves at the end of ventricular systole.
- Electrocardiogram (ECG): A graphical recording of the electrical activity of the heart during a cardiac cycle, used to detect abnormalities. Measured using an electrocardiograph.

B. Blood Vessels

Function: A network of hollow, tube-like structures connected to the heart that transport blood throughout the body.
Types:

Type	Function	Characteristics	Flow Direction	Exceptions
Arteries	Carry blood away from the heart, usually oxygenated.	Thick, elastic, muscular walls to withstand high pressure; branch into arterioles.	Away from Heart	Pulmonary Artery (carries deoxygenated blood)
Veins	Carry blood towards the heart, usually deoxygenated.	Thinner walls than arteries; contain valves (especially in limbs) to prevent backflow; formed from venules.	Towards Heart	Pulmonary Veins (carry oxygenated blood)
Capillaries	Smallest vessels connecting arterioles and venules; form extensive networks.	Extremely thin walls (single cell layer) facilitating efficient exchange of gases (O₂, CO₂), nutrients, and waste products between blood and body tissues.	Between Arteries & Veins	N/A

C. Blood

Function: A specialized fluid connective tissue that circulates throughout the body, serving as the primary transport medium. Also involved in protection (immunity) and temperature regulation.
Production: Blood cells are manufactured in the bone marrow (process called haemopoiesis).
Composition: Consists of plasma and formed elements (blood cells).

Component	Description / Key Features	Function
Plasma	Liquid matrix (~55% of blood volume); straw-colored, viscous fluid, mostly water. Contains proteins (albumin, globulin, fibrinogen), salts, hormones, nutrients, waste products.	Transports dissolved substances (nutrients, wastes, hormones, proteins, CO₂); maintains blood volume and pressure.
Formed Elements (Cells):
Red Blood Cells (RBCs) / Erythrocytes	Biconcave discs (in mammals), lack a nucleus when mature. Contain Hemoglobin, an iron-rich red pigment. Most numerous blood cell type.	Transport oxygen from lungs to tissues via hemoglobin; transport some carbon dioxide from tissues to lungs.
White Blood Cells (WBCs) / Leucocytes	Larger than RBCs, possess a nucleus, colorless, irregular shapes. Several types exist (e.g., neutrophils, lymphocytes).	Part of the immune system; defend against infection and disease by engulfing pathogens or producing antibodies.
Platelets / Thrombocytes	Small, irregular cell fragments, lack a nucleus.	Initiate blood clotting (coagulation/hemostasis) at injury sites to prevent excessive blood loss.

Blood Groups: Humans have different blood groups based on antigens on RBC surfaces (e.g., A, B, AB, O system).
- Universal Donor: Blood group O (can donate to A, B, AB, O).
- Universal Recipient: Blood group AB (can receive from A, B, AB, O).

D. Circulation Pathways (Double Circulation)

Blood passes through the heart twice for each complete circuit of the body. This ensures efficient oxygenation and separation of oxygenated/deoxygenated blood.
1. Pulmonary Circulation: (Heart <-> Lungs)
- Deoxygenated blood leaves the Right Ventricle.
- Travels via the Pulmonary Artery to the Lungs.
- In lung capillaries (alveoli), CO₂ is released, and O₂ is picked up.
- Oxygenated blood returns from the lungs via the Pulmonary Veins to the Left Atrium.
2. Systemic Circulation: (Heart <-> Rest of the Body)
- Oxygenated blood leaves the Left Ventricle.
- Travels via the Aorta and branching arteries to all body tissues.
- In body capillaries, O₂ and nutrients are delivered to cells, and CO₂ and waste products are picked up.
- Deoxygenated blood returns from the tissues via veins, ultimately collecting in the Superior and Inferior Vena Cava, which empty into the Right Atrium.
3. Portal Circulation (Specific Systemic Pathway):
- A system where blood flows from one capillary network to another via a portal vein before returning to the heart.
- Example: Hepatic Portal System: Blood from capillaries in the stomach and intestines flows through the Hepatic Portal Vein to capillaries (sinusoids) in the Liver. This allows the liver to process absorbed nutrients and detoxify substances before they enter the general systemic circulation via the hepatic vein.

E. Heartbeat and Blood Pressure

Heartbeat: The rhythmic cycle of contraction (systole) and relaxation (diastole) of the heart chambers. Rate is ~70-80 bpm at rest.
Blood Pressure: The force exerted by circulating blood against the walls of arteries.
- Measured using a sphygmomanometer in millimeters of mercury (mmHg).
- Systolic Pressure: Maximum pressure during ventricular contraction (normal ≈ 120 mmHg).
- Diastolic Pressure: Minimum pressure during ventricular relaxation (normal ≈ 80 mmHg).
- Written as Systolic/Diastolic (e.g., 120/80 mmHg).

F. Diseases and Disorders Related to the Circulatory System

Disease/Disorder	Description / Cause	Common Symptoms / Consequences
Hypertension	Persistently high blood pressure (e.g., >140/90 mmHg). Can be caused by constricted arterioles, increasing resistance.	Often asymptomatic initially; headache, dizziness. Increases risk of heart attack, stroke, kidney failure, artery rupture.
Coronary Artery Disease (CAD) / Atherosclerosis / Arteriosclerosis	Narrowing or blockage of coronary arteries (supplying heart muscle) due to plaque buildup (fat, cholesterol).	Chest pain (angina), shortness of breath; can lead to Heart Attack.
Heart Attack (Myocardial Infarction)	Blockage of blood flow to a part of the heart muscle, causing tissue damage or death.	Severe chest pain/pressure, pain radiating to arm/jaw, shortness of breath, sweating, nausea.
Heart Failure	The heart muscle weakens and cannot pump blood effectively to meet the body's needs.	Fatigue, shortness of breath, swelling in legs/ankles/abdomen (edema).
Cardiac Arrest	Sudden, abrupt loss of heart function due to an electrical disturbance, leading to cessation of blood flow.	Sudden collapse, unconsciousness, no breathing, no pulse. Medical emergency.
Anemia	Deficiency in the number of Red Blood Cells or the amount of Hemoglobin within them.	Fatigue, weakness, pallor (pale skin), shortness of breath, dizziness.
Varicose Veins	Swollen, twisted veins, often visible in the legs, caused by weakened valves allowing blood to pool.	Visible, bulging veins; aching, heaviness, swelling, itching in legs.
Leukemia	Cancer of blood-forming tissues, including bone marrow, leading to an overproduction of abnormal White Blood Cells.	Varies; fatigue, infections, bruising, weight loss.
Leukopenia	A decrease in the number of White Blood Cells.	Increased susceptibility to infections.
Polycythemia	An abnormal increase in the number of Red Blood Cells.	Can cause thickened blood, increasing clotting risk; headache, dizziness.

G. Tips for a Healthy Circulatory System

Eat a Healthy Diet: Emphasize fruits, vegetables, whole grains. Limit saturated/trans fats, cholesterol, sodium, and added sugars.
Exercise Regularly: Aim for at least 30 minutes of moderate-intensity activity (like brisk walking) most days of the week.
Avoid Smoking: Smoking damages blood vessels and the heart significantly.
Limit Alcohol Consumption: Excessive alcohol intake can raise blood pressure and harm the heart.
Manage Stress: Chronic stress can negatively impact heart rate and blood pressure. Practice relaxation techniques (meditation, yoga, deep breathing).
Stay Hydrated: Drink sufficient water to maintain adequate blood volume and flow.
Get Regular Health Checkups: Monitor blood pressure, cholesterol levels, and blood sugar to detect potential issues early.

Ch-7 Digestive System in Human Being

I. Overview and Function

Definition: A complex system responsible for processing food, breaking down complex substances into simpler, absorbable molecules to provide the body with nutrients and energy.
Components: Consists of the Alimentary Canal (a long, continuous tube) and Accessory Digestive Glands (which secrete essential substances for digestion).
Alimentary Canal Length: Approximately 8-10 meters (or ~9 meters) long, extending from the mouth to the anus.
Overall Process: Involves ingestion, propulsion, mechanical and chemical digestion, absorption, assimilation, and egestion.

II. Components of the Digestive System

A. The Alimentary Canal (Pathway of Food)

A continuous tube with specialized regions for different functions. Its wall (from esophagus to rectum) generally consists of four layers:
1. Serosa: Outermost layer.
2. Muscularis: Smooth muscle layers (responsible for peristalsis and churning).
3. Sub-mucosa: Connective tissue with nerves, blood, and lymph vessels.
4. Mucosa: Innermost lining, secretes mucus and digestive enzymes/juices. Forms folds (rugae in stomach, villi in small intestine).

Part	Description & Location	Key Functions & Features	Digestion/Absorption Notes
1. Mouth & Buccal Cavity (Oral Cavity)	Anterior opening and the space within. Contains teeth, tongue, salivary gland openings.	Ingestion (taking in food). Mechanical Digestion: Chewing (mastication by teeth). Mixing: Tongue mixes food with saliva, forms bolus. Tasting: Taste buds on tongue. Swallowing initiation.	Chemical Digestion: Salivary amylase begins starch breakdown. Absorption: Some drugs absorbed through mucosa.
2. Pharynx (Throat)	Cavity at the back of the mouth; common passage for food and air.	Pushes food bolus towards esophagus during swallowing (deglutition).	None.
3. Esophagus (Food Pipe)	Muscular tube (~25 cm long) connecting pharynx to stomach.	Transports food bolus from pharynx to stomach via Peristalsis (wave-like muscular contractions).	No digestion or significant absorption occurs here.
4. Stomach	J-shaped/U-shaped elastic, muscular sac in the upper left abdomen, below the diaphragm. Widest part of the canal.	Storage: Holds food for ~3-4 hours. Mechanical Digestion: Churning action mixes food with gastric juice. Chemical Digestion: Secretes Gastric Juice (HCl, Pepsin, Rennin). Forms acidic chyme. Mucosa has folds (rugae).	Chemical Digestion: Pepsin (activated by HCl) begins protein breakdown. Rennin aids milk digestion (esp. infants). Absorption: Water, simple sugars, alcohol.
5. Small Intestine	Longest part (~6-7.5 meters), highly coiled tube filling much of the abdomen.	Primary site for chemical digestion completion and nutrient absorption. Receives secretions from liver, gallbladder, pancreas. Divided into: Duodenum (initial section), Jejunum (middle section), Ileum (final section). Enhanced surface area due to villi and microvilli.	Chemical Digestion: Enzymes from pancreas and intestinal wall digest carbohydrates, proteins, fats. Absorption: Principal site for absorbing glucose, amino acids, fatty acids, glycerol, vitamins, minerals, water.
6. Large Intestine	Wider but shorter (~1.5 meters) tube surrounding the small intestine.	Absorption: Absorbs water, minerals (electrolytes), and some drugs from remaining indigestible material. Formation & Storage: Forms and stores feces. Secretion: Secretes mucus for lubrication. Divided into: Caecum (pouch with vermiform appendix), Colon (ascending, transverse, descending, sigmoid), Rectum.	No significant digestive enzyme activity. Bacteria here synthesize some vitamins (e.g., Vitamin K).
7. Rectum	Final section of the large intestine (~15-20 cm).	Temporarily stores feces before elimination.	Absorption of water and electrolytes continues.
8. Anus	Posterior external opening of the alimentary canal.	Egestion (Defecation): Expels feces from the body. Controlled by internal and external anal sphincter muscles.	None.

Villi: Small, finger-like projections lining the mucosa of the small intestine. They vastly increase the surface area for efficient nutrient absorption. Each villus contains a network of blood capillaries (for absorbing sugars, amino acids, etc.) and a lymph capillary called a lacteal (for absorbing fats).

B. Accessory Digestive Glands

Glands located outside the alimentary canal that secrete substances essential for digestion via ducts.

Gland	Location	Secretion(s)	Key Components & Functions of Secretion
1. Salivary Glands	In/around the buccal cavity (Parotid, Submandibular/Submaxillary, Sublingual).	Saliva	Contains Salivary Amylase (Ptyalin/Tylin): Begins starch digestion (starch → maltose/dextrins). Contains mucus: Lubricates food, forms bolus for swallowing. Contains electrolytes and antibacterial compounds (e.g., lysozyme).
2. Liver	Upper right abdomen, below the diaphragm. Largest gland (~1.2-1.5 kg).	Bile Juice	Bile: Emulsifies fats (breaks large fat globules into smaller droplets), increasing surface area for lipase action. Contains bile salts, bile pigments (bilirubin, biliverdin - from RBC breakdown), cholesterol, phospholipids. Note: Bile contains no digestive enzymes. Other liver functions: Detoxification, metabolism, glycogen storage.
3. Gallbladder	Small, pear-shaped sac tucked beneath the liver.	Stores & concentrates Bile.	Releases stored bile into the small intestine (duodenum) via the bile duct when needed (especially after a fatty meal).
4. Pancreas	Behind the stomach, in the curve of the duodenum. Cream-colored/reddish-brown.	Pancreatic Juice (Exocrine function)	Contains several powerful digestive enzymes: Pancreatic Amylase: Digests starch. Trypsin (and Chymotrypsin): Digest proteins/peptides. Pancreatic Lipase: Digests fats (triglycerides) → fatty acids + glycerol. Contains bicarbonate: Neutralizes acidic chyme from the stomach.
		Hormones (Insulin, Glucagon) (Endocrine function)	Regulate blood sugar levels (secreted directly into bloodstream, not involved in digestion within the canal).
5. Gastric Glands	In the stomach wall mucosa.	Gastric Juice	Contains HCl: Creates acidic pH (~1.5-3.5), kills microbes, activates pepsinogen → pepsin. Pepsin(ogen): Begins protein digestion. Rennin: Curdles milk protein (infants). Mucus: Protects stomach lining from acid.
6. Intestinal Glands	In the small intestine wall mucosa (Crypts of Lieberkühn).	Intestinal Juice (Succus Entericus)	Contains enzymes for final digestion: Disaccharidases (Maltase, Sucrase, Lactase): Break down disaccharides → monosaccharides. Peptidases: Break down small peptides → amino acids. Lipase: (Minor role). Contains mucus and bicarbonate.

III. The Process of Digestion in Humans (Stages)

Human nutrition (Holozoic) involves the following steps:

Ingestion: Taking food into the mouth/oral cavity.
Propulsion: Movement of food through the alimentary canal.
- Swallowing (Deglutition): Moving the bolus from the mouth, through the pharynx, into the esophagus.
- Peristalsis: Rhythmic, wave-like muscular contractions that push food along the esophagus, stomach, and intestines.
Digestion: Breakdown of complex, non-absorbable food molecules into simpler, absorbable molecules.
- Mechanical Digestion: Physical breakdown of food (chewing, churning in the stomach, segmentation in the small intestine).
- Chemical Digestion: Breakdown using enzymes secreted by glands and the canal wall . Occurs in the mouth, stomach, and primarily the small intestine.
Absorption: Passage of digested end products (nutrients) from the lumen of the GI tract, across the mucosal cells, into the blood or lymph.
- Primary Site: Small intestine (vast surface area due to villi/microvilli).
- Absorption Routes:
  - Simple sugars (glucose, fructose, galactose), amino acids, water-soluble vitamins, minerals, water → Blood capillaries within villi.
  - Fatty acids, glycerol (re-esterified into triglycerides), fat-soluble vitamins → Packaged into chylomicrons → Lacteals (lymph capillaries) within villi.
- Other Sites: Some water, alcohol, simple sugars (stomach); water, electrolytes, some vitamins (large intestine); certain drugs (mouth, stomach, large intestine).
Assimilation: Utilization of the absorbed nutrients by the body's cells for energy production, growth, repair, and synthesis of new complex molecules (e.g., proteins).
Egestion (Defecation): Elimination of undigested, unabsorbed waste materials (feces) from the body via the anus. Involves compaction in the large intestine and storage in the rectum.

IV. Chemical Digestion: Summary of Key Enzymes

Enzymes are biological catalysts (proteins) that speed up the breakdown of food molecules.

Location	Source	Enzyme(s)	Substrate(s)	Product(s)	Optimal pH	Notes
Mouth	Salivary Glands	Salivary Amylase (Ptyalin)	Starch (Carbohydrate)	Maltose, Dextrins (Smaller polysaccharides)	~6.7-7.0	Action stops in stomach acid
Stomach	Gastric Glands	Pepsin	Proteins	Peptides (Smaller polypeptides)	~1.5-3.5	Secreted as inactive Pepsinogen, activated by HCl
		Rennin	Milk Protein (Casein)	Curdles milk	Acidic	Primarily in infants
Small Intestine	Pancreas	Pancreatic Amylase	Starch, Dextrins	Maltose, Disaccharides	Alkaline
	(Pancreatic Juice)	Trypsin (and Chymotrypsin)	Proteins, Peptides	Smaller Peptides	Alkaline	Secreted as inactive Trypsinogen, activated by Enterokinase
		Pancreatic Lipase	Fats (Triglycerides)	Fatty Acids + Glycerol	Alkaline	Requires bile for efficiency
	Intestinal Wall	Disaccharidases:			Alkaline
	(Intestinal Juice)	* Maltase	Maltose	Glucose + Glucose
		* Sucrase	Sucrose	Glucose + Fructose
		* Lactase	Lactose	Glucose + Galactose		Lactose intolerance if deficient
		Peptidases (Aminopeptidase, Dipeptidase)	Small Peptides, Dipeptides	Amino Acids	Alkaline	Final protein digestion
		Intestinal Lipase	Fats (Triglycerides)	Fatty Acids + Glycerol	Alkaline	Minor contribution

V. Regulation of Digestion

The activities of the digestive system are coordinated and controlled by:
- Neural Control: Intrinsic nerve plexuses within the gut wall (Enteric Nervous System) and extrinsic nerves (Autonomic Nervous System - sympathetic and parasympathetic).
- Hormonal Control: Gastrointestinal hormones (e.g., Gastrin stimulates stomach activity, Secretin stimulates bicarbonate release from pancreas, Cholecystokinin (CCK) stimulates pancreatic enzyme release and gallbladder contraction) regulate secretions and motility.
Immune Function: Mucosa-Associated Lymphoid Tissue (MALT) within the alimentary canal helps protect against pathogens.

VI. Digestive System Disorders

Inflammation: Of the intestinal tract (e.g., gastroenteritis) due to infections (bacterial, viral) or parasites.
Jaundice: Yellowing of skin and eyes due to deposition of bile pigments (bilirubin), often indicating liver problems (e.g., hepatitis).
Vomiting: Forceful ejection of stomach contents; a reflex controlled by the medulla oblongata.
Diarrhoea: Frequent, loose, watery stools; leads to reduced absorption and risk of dehydration (ORS recommended).
Constipation: Infrequent or difficult defecation; feces retained in the rectum.
Indigestion (Dyspepsia): Feeling of fullness, discomfort, or pain in the upper abdomen, often due to improper digestion (causes: inadequate enzymes, anxiety, food poisoning, overeating, spicy food).

Ch-8 Blood Groups, Blood Composition, and Function

I. Blood: Definition and Overview

Definition: Blood is a red-coloured, thick, slightly alkaline fluid connective tissue that circulates within blood vessels.
Role: It serves as the main circulating fluid, essential for transporting various substances throughout the body.
Origin: Blood cells are manufactured in the bone marrow through a process called haemopoiesis.

II. Composition of Blood

Blood consists of two main components: Plasma (the fluid matrix) and Formed Elements (cells and cell fragments).

A. Plasma

Proportion: Constitutes approximately 55% of total blood volume.
Appearance: Straw-coloured, viscous fluid.
Composition:
- Water: ~90-92%
- Proteins (6-8%):
  - Fibrinogen (Essential for clotting)
  - Globulins (Involved in defense mechanisms)
  - Albumins (Help maintain osmotic balance)
- Minerals: Small amounts of Na+, Ca++, Mg++, HCO3–, Cl–, etc.
- Nutrients: Glucose, amino acids, lipids (in transit).
- Gases: Dissolved O₂, CO₂.
- Hormones & Enzymes: Transported via plasma.
- Waste Products: Transported for excretion.
- Clotting Factors: Present in an inactive form (including Prothrombin, produced by the liver along with Fibrinogen).
Serum: Plasma from which clotting factors (like fibrinogen) have been removed.

B. Formed Elements (Blood Cells & Platelets)

Proportion: Constitute approximately 45% of total blood volume.

Types: Erythrocytes (RBCs), Leucocytes (WBCs), and Platelets (Thrombocytes).

1. Red Blood Cells (RBCs / Erythrocytes)

Structure: Circular, biconcave disc-like shape; lack a nucleus in mature humans.
Pigment: Contain Haemoglobin, a red-coloured protein responsible for the blood's colour.
Function: Transport **Oxygen (O₂) **from lungs to tissues and **Carbon Dioxide (CO₂) **from tissues to lungs, bound primarily to haemoglobin. Efficient O₂ transport relies heavily on haemoglobin.
Formation: Produced in the bone marrow.
Lifespan: Approximately 120 days.
Normal Count: About 5 million per cubic millimeter (mm³).
Related Conditions:
- Polycythemia: Increased RBC count.
- Anemia: Decreased RBC count (Iron in diet helps prevent/treat some forms).

2. White Blood Cells (WBCs / Leucocytes)

Structure: Irregular shape; possess a nucleus (shape varies with type); colourless (lack pigment).
Function: Part of the immune system; protect the body against infection and disease by destroying pathogens (e.g., bacteria, viruses) or producing antibodies.
Lifespan: Approximately 12-20 days.
Types and Specific Roles:

WBC Type	Primary Role
Neutrophils	Phagocytize (eat) bacteria and fungi.
Lymphocytes	Responsible for specific immune responses. Two main types: - B-lymphocytes: Produce antibodies. - T-lymphocytes: Help B-cells, identify & destroy infected cells/antigens.
Monocytes	Phagocytize pathogens and cellular debris; help eliminate infections.
Eosinophils	Combat parasitic infections; involved in allergic reactions.
Basophils	Release histamine and other mediators involved in inflammation and allergic reactions.

Related Conditions:
- Leukemia: Cancer characterized by an abnormal increase in WBCs.
- Leukopenia: Decreased WBC count.

3. Platelets (Thrombocytes)

Structure: Very small, irregular cell fragments; lack nuclei.
Function: Essential for blood clotting (coagulation); release substances that initiate clotting to stop bleeding.
Formation: Produced from large cells called megakaryocytes in the bone marrow.
Lifespan: Approximately 8-10 days.
Normal Count: About 1,500,000 - 3,500,000 per cubic millimeter (mm³).
Related Conditions: Reduction in platelet count can lead to clotting disorders and excessive bleeding (haemorrhage).

III. Functions of Blood

Blood performs numerous vital functions:

Transport:
- Gases: Carries O₂ from lungs to body cells and CO₂ from body cells to lungs (via RBCs/Haemoglobin).
- Nutrients: Transports digested food products (glucose, amino acids, lipids, vitamins, minerals) from the small intestine to body cells.
- Waste Products: Carries metabolic wastes (e.g., urea) to excretory organs (like kidneys) for removal.
- Hormones & Enzymes: Distributes hormones from endocrine glands and enzymes to target sites.
- Water: Distributes water throughout the body.
- Medicines: Helps distribute certain medications.
Protection & Immunity:
- WBCs defend against pathogens (bacteria, viruses, etc.) through phagocytosis and antibody production (lymphocytes).
Blood Clotting (Coagulation):
- Platelets and plasma proteins (like Fibrinogen) form clots to prevent excessive blood loss upon injury.
Regulation:
- Body Temperature: Helps distribute heat and maintain a stable body temperature.
- Acid-Base Balance (pH): Helps maintain the body's pH equilibrium.
- Osmotic Balance: Plasma proteins help maintain fluid balance between blood and tissues.

IV. Blood Clotting (Coagulation)

Definition: The process of blood thickening to form a clot (scab) at the site of vessel injury, preventing further blood loss.
Mechanism: A complex process involving:
- Platelets: Aggregate at the injury site and release clotting factors.
- Plasma Proteins: Primarily Fibrinogen (inactive) is converted to Fibrin (insoluble fibres). Prothrombin is another key inactive protein. Both are produced by the liver.
- Fibrin: Forms a meshwork that traps blood cells (especially RBCs), forming the clot.
Requirements:
- Calcium ions (Ca++): Essential cofactor in the clotting cascade.
- Vitamin K: Necessary for the liver to synthesize prothrombin and other clotting factors.
Regulation: Heparin (produced by the liver) is an anticoagulant that helps prevent unwanted clotting within blood vessels.
Disorders: Haemophilia is a genetic disorder where blood fails to clot properly.

V. Blood Groups

Definition: Classification of blood based on the presence or absence of specific inherited antigens (substances that can trigger an immune response) on the surface of Red Blood Cells (RBCs) and corresponding antibodies (proteins that react with specific antigens) in the plasma.
Importance: Crucial for safe blood transfusions, as mixing incompatible blood types causes agglutination (clumping) of RBCs, which can be fatal.
Major Systems: ABO and Rh are the most clinically significant.

A. ABO Blood Group System

Discovery: Karl Landsteiner (1901).
Basis: Presence or absence of two antigens (A and B) on RBCs and two natural antibodies (Anti-A and Anti-B) in plasma.
Genetics: Controlled by the gene 'I' with three alleles: Iᴬ, Iᴮ, and i.
- Iᴬ and Iᴮ are codominant (both expressed if present together) and produce A and B antigens, respectively.
- 'i' is recessive and produces no antigen.
Blood Types:

Blood Group	Genotype(s)	Antigen(s) on RBC	Antibody(ies) in Plasma	Can Donate To	Can Receive From
A	IᴬIᴬ or Iᴬi	A	Anti-B	A, AB	A, O
B	IᴮIᴮ or Iᴮi	B	Anti-A	B, AB	B, O
AB	IᴬIᴮ	A and B	None	AB only	A, B, AB, O
O	ii	None	Anti-A and Anti-B	A, B, AB, O	O only

Universal Donor: Group O (lacks A and B antigens, so RBCs won't be agglutinated by recipient's antibodies).
Universal Recipient: Group AB (lacks Anti-A and Anti-B antibodies, so won't agglutinate donor RBCs).

B. Rh Blood Group System

Basis: Presence or absence of the Rh antigen (also called D antigen) on the surface of RBCs.
Types:
- Rh Positive (Rh+): Rh antigen is present (approx. 80% of humans).
- Rh Negative (Rh-): Rh antigen is absent.
Clinical Significance:
- Transfusion: An Rh- person exposed to Rh+ blood (e.g., via transfusion) will develop Anti-Rh antibodies. Subsequent exposure to Rh+ blood can cause a severe transfusion reaction. Rh group matching is essential.
- Pregnancy (Rh Incompatibility): If an Rh- mother carries an Rh+ fetus, fetal RBCs entering the mother's circulation can cause her to produce Anti-Rh antibodies. In subsequent Rh+ pregnancies, these antibodies can cross the placenta and destroy fetal RBCs (causing Hemolytic Disease of the Newborn).

Ch-9 Hormones

I. Introduction to Hormones

Definition: Hormones are non-nutrient chemical compounds or messengers produced in trace amounts, acting as intercellular messengers. They are biologically very active.
Secretion: Secreted by specialized endocrine glands (ductless glands) directly into the bloodstream. Some diffused tissues/cells also produce hormones.
Transport: Carried by the bloodstream to target organs or tissues, which may be located far from the gland.
Function: Provide chemical coordination, integration, and regulation in the human body. They stimulate specific activities in their target tissues, regulating functions like metabolism, growth, development, reproduction, immunity, stress response, sleep-wake cycles, and maintaining homeostasis.
Coordination: The endocrine system works jointly with the neural system to coordinate and regulate physiological functions.

II. Characteristics and Chemical Nature of Hormones

Key Characteristics:
- Secreted directly into the bloodstream (ductless gland secretion).
- Transported via blood to target specific organs/tissues.
- Act on target tissues by binding to specific protein receptors.
- Produced in very small (trace) amounts but are highly active.
- Often have slow but potentially long-lasting effects compared to nerve impulses.
- Regulated, typically by feedback mechanisms.
- Imbalances (excess or deficiency) can lead to serious disorders.
Chemical Diversity: Hormones vary chemically:
- Steroids: Lipid-soluble. Examples include:
  - Estrogens (e.g., Estradiol)
  - Androgens (e.g., Testosterone)
  - Progesterone
  - Adrenocortical hormones (Glucocorticoids, Mineralocorticoids)
- Polypeptides/Proteins/Glycoproteins: Water-soluble. Examples include:
  - Insulin
  - Glucagon
  - Pituitary hormones (GH, TSH, LH, FSH, etc.)
  - Endorphins
  - Hypothalamic hormones
- Amino Acid Derivatives: Some are water-soluble (amines), others lipid-soluble (iodothyronines). Examples include:
  - Epinephrine (Adrenaline) & Norepinephrine (Noradrenaline) - derived from tyrosine.
  - Thyroid hormones (Thyroxine, Triiodothyronine) - iodinated tyrosine derivatives.
  - Melatonin - derived from tryptophan.

III. Mechanism of Hormone Action

Receptor Binding: Hormones exert their effects by binding to specific protein hormone receptors located on or inside target cells.
Receptor Location & Action:
- Membrane-Bound Receptors: Located on the cell surface. Hormones binding here (typically water-soluble ones like polypeptides, catecholamines) usually:
  - Do not enter the target cell.
  - Generate second messengers (e.g., cyclic AMP (cAMP), IP₃, Ca++).
  - These second messengers then activate existing enzymes and regulate cellular metabolism.
- Intracellular Receptors: Located inside the target cell, usually in the cytoplasm or nucleus. Hormones binding here (typically lipid-soluble ones like steroids and iodothyronines):
  - Enter the cell.
  - Interact mostly with nuclear receptors.
  - The hormone-receptor complex binds to the genome (DNA).
  - This interaction regulates gene expression or chromosome function, leading to the synthesis of specific proteins.
Outcome: These biochemical actions at the cellular level result in the broader physiological and developmental effects associated with the hormone (e.g., changes in metabolism, growth, cell division).

IV. The Human Endocrine System

Consists of organized endocrine glands and hormone-producing diffused tissues/cells throughout the body.

A. Major Endocrine Glands & Their Hormones

Gland	Location	Key Hormone(s)	Primary Function(s)
Hypothalamus	Base of the forebrain (diencephalon)	- Releasing Hormones (e.g., GnRH, TRH) - Inhibiting Hormones (e.g., Somatostatin) - Oxytocin & Vasopressin (ADH) (produced here)	Controls pituitary gland secretions; regulates temperature, hunger, thirst, emotions, sexual behavior; Oxytocin & ADH transported to posterior pituitary for release.
Pituitary Gland ("Master Gland")	Base of brain (in sella turcica), attached to hypothalamus	Anterior Pituitary (Adenohypophysis): - Growth Hormone (GH) - Prolactin (PRL) - Thyroid Stimulating Hormone (TSH) - Adrenocorticotropic Hormone (ACTH) - Luteinizing Hormone (LH) - Follicle Stimulating Hormone (FSH) Pars Intermedia: - Melanocyte Stimulating Hormone (MSH) Posterior Pituitary (Neurohypophysis): - Stores & Releases: Oxytocin, Vasopressin (ADH)	Controls many other endocrine glands. GH: Body growth. PRL: Milk production. TSH: Stimulates thyroid. ACTH: Stimulates adrenal cortex. LH & FSH (Gonadotropins): Stimulate gonads (testes/ovaries) for gamete production & hormone secretion; regulate menstrual cycle (follicular development, estrogen secretion, ovulation). MSH: Skin pigmentation. Oxytocin: Uterine contraction (childbirth), milk ejection. ADH: Kidney water reabsorption.
Pineal Gland	Dorsal side of forebrain	Melatonin	Regulates circadian rhythms (sleep-wake cycle), timing of puberty.
Thyroid Gland	Neck, on the trachea	- Thyroxine (T4) & Triiodothyronine (T3) (Iodothyronines) - Thyrocalcitonin (Calcitonin)	T3/T4: Regulate basal metabolic rate, support RBC formation, control metabolism of carbs/proteins/fats, CNS development. Requires iodine. Calcitonin: Lowers blood calcium levels.
Parathyroid Glands	Back side of the thyroid gland (usually 4)	Parathyroid Hormone (PTH)	Increases blood calcium levels (by acting on bones, kidneys, intestine).
Thymus	Behind sternum, above heart (degenerates with age)	Thymosins	Crucial for immune system development. Promote differentiation of T-lymphocytes (cell-mediated immunity) & promote antibody production (humoral immunity). Degeneration leads to weaker immunity in old age.
Adrenal Glands	Top of each kidney	Adrenal Cortex: - Glucocorticoids (e.g., Cortisol) - Mineralocorticoids (e.g., Aldosterone) - Androgenic Steroids Adrenal Medulla: - Epinephrine (Adrenaline) - Norepinephrine (Noradrenaline)	Cortex: Glucocorticoids: Carbohydrate metabolism, anti-inflammatory, stress response. Mineralocorticoids: Regulate water & electrolyte balance (Na+, K+ excretion by kidney), blood pressure. Androgens: Minor role in secondary sex characters. Medulla: "Fight-or-flight" response, increase alertness, heart rate, respiration rate, blood glucose.
Pancreas (Mixed gland)	Near duodenum	Islets of Langerhans: - Insulin (from β-cells) - Glucagon (from α-cells)	Regulate blood glucose levels. Insulin: Lowers blood glucose (promotes uptake & utilization). Glucagon: Raises blood glucose (promotes glycogenolysis & gluconeogenesis).
Gonads	Pelvic region	Testes (Male): - Androgens (e.g., Testosterone, Androsterone) Ovaries (Female): - Estrogens (e.g., Estradiol) - Progesterone	Responsible for primary sex characteristics & gamete production. Testosterone: Spermatogenesis, development of male secondary sex characters (facial hair, deep voice, etc.), libido, anabolic effects. Estrogens: Development of female secondary sex characters (high pitch voice, mammary glands), regulate menstrual cycle, female sexual behavior. Progesterone: Supports pregnancy, prepares mammary glands (alveoli formation, milk secretion).

B. Other Hormone-Producing Tissues

Tissue/Organ	Hormone(s)	Primary Function(s)
Heart (Atrial Wall)	Atrial Natriuretic Factor (ANF) / Antinatriuretic Factor	Decreases blood pressure (by causing vasodilation & Na+/water excretion); involved in water, Na+, K+, fat homeostasis.
Kidneys	Erythropoietin (EPO)	Stimulates erythropoiesis (RBC formation) in bone marrow.
Gastrointestinal Tract	Gastrin, Secretin, Cholecystokinin (CCK), Gastric Inhibitory Peptide (GIP)	Regulate digestive processes (e.g., stimulate acid/enzyme/bicarbonate secretion, bile release, inhibit gastric activity).
Placenta (Temporary)	hCG, hPL, Estrogens, Progesterone	Maintain pregnancy, support fetal growth, prepare mammary glands for lactation.

V. Hormonal Regulation and Roles in Life Processes

Regulation: Hormone secretion is precisely regulated, often by feedback mechanisms (usually negative feedback). The hypothalamus plays a key role in linking the nervous and endocrine systems to control many hormonal pathways (e.g., Hypothalamic-Pituitary-Adrenal axis, Hypothalamic-Pituitary-Gonadal axis).
Life Processes:
- Metabolism: Hormones like insulin, glucagon, thyroid hormones, cortisol regulate nutrient metabolism.
- Growth & Development: GH, thyroid hormones, sex hormones are critical for growth and maturation.
- Reproduction: Gonadotropins (LH, FSH) and sex hormones (estrogen, progesterone, testosterone) regulate gamete production, the menstrual cycle, development of secondary sex characteristics, sexual behavior, and pregnancy. Environmental factors can interact with hormones to regulate reproduction.
- Childbirth (Parturition): A complex neuroendocrine mechanism involving cortisol, estrogens, and oxytocin.
- Stress Response: Cortisol, adrenaline, noradrenaline help the body cope with stress.
- Immunity: Thymosins are crucial for immune cell development. Glucocorticoids modulate immune/inflammatory responses.
- Homeostasis: Hormones maintain internal balance of fluids, electrolytes, temperature, blood pressure, and glucose.

VI. Hormonal Imbalances and Disorders

Excess (hypersecretion) or deficiency (hyposecretion) of hormones can cause various physiological disorders.

Hormone Category/Example	Common Disorder(s) due to Excess (Hypersecretion)	Common Disorder(s) due to Deficiency (Hyposecretion)
Growth Hormone (GH)	Gigantism (children), Acromegaly (adults)	Pituitary Dwarfism (children)
Thyroid Hormones (T3/T4)	Hyperthyroidism (e.g., Graves' Disease)	Hypothyroidism (e.g., Goitre, Cretinism (children), Myxedema (adults))
Parathyroid Hormone (PTH)	Hyperparathyroidism (Hypercalcemia, bone issues)	Hypoparathyroidism (Hypocalcemia, tetany)
Cortisol (Glucocorticoid)	Cushing's Syndrome/Disease	Addison's Disease
Insulin	Hypoglycemia (often due to overdose)	Diabetes Mellitus (Type 1 or insufficient in Type 2)
ADH (Vasopressin)	SIADH (Syndrome of Inappropriate ADH Secretion)	Diabetes Insipidus
Adrenaline/Noradrenaline	Hypertension, Anxiety (e.g., Pheochromocytoma)	Less commonly associated with specific deficiency syndromes

Ch-10 Genetic and Lifestyle Diseases

I. Introduction: Classification of Diseases

Definition: Diseases are classified into major categories.
Main Categories:
- Genetic Diseases: Transferred from parents to offspring through DNA (genes).
- Lifestyle Diseases: Caused by external factors like poor diet, lack of physical activity, stress, unhealthy habits, etc.

II. Genetic Diseases

Basis: Inherited from parents to children via genes.
Major Genetic Diseases:
1. Hemophilia:
  - Description: X-chromosome-linked disorder where blood does not clot properly.
  - Effect: Excessive bleeding can occur after injury.
  - Prevalence: More common in men.
2. Thalassemia:
  - Description: Genetic blood disorder producing less hemoglobin.
  - Effect: Requires frequent blood transfusions.
3. Sickle Cell Anemia:
  - Description: Red blood cells (RBCs) become sickle-shaped, impairing oxygen transport.
  - Effect: Causes oxygen deficiency, fatigue, and joint pain.
4. Huntington's Disease:
  - Description: Genetic disorder affecting nervous system (brain cells).
  - Effect: Symptoms include memory loss, muscle imbalance, and mental disorders.
5. Down Syndrome:
  - Cause: Abnormality in chromosome number (Trisomy 21).
  - Effect: Intellectual disability, slow physical development, higher chance of heart disease.
6. Color Blindness:
  - Cause: Deficiency of color-detecting cells in the retina.
  - Effect: Difficulty differentiating between red and green colors.
7. Muscular Dystrophy:
  - Description: Genetic disorder weakening and destroying muscles.
  - Effect: Gradual loss of mobility (e.g., ability to walk).

III. Lifestyle Diseases

Basis: Arise due to poor diet, stress, physical inactivity, and other unhealthy habits.
Major Lifestyle Diseases:
1. Diabetes Mellitus:
  - Description: Imbalance of blood sugar levels.
  - Types:
    - Type-1: Body does not produce insulin.
    - Type-2: Body does not utilize insulin properly.
  - Main Causes: Unhealthy diet, obesity, stress, lack of physical activity.
2. Hypertension (High Blood Pressure):
  - Description: Blood pressure exceeds the normal level (normal: 120/80 mmHg).
  - Main Causes: Excess salt/fat intake, obesity, smoking, stress, lack of exercise.
3. Cardiovascular Diseases (CVDs):
  - Examples: Heart attacks, strokes, atherosclerosis.
  - Main Causes: High cholesterol, smoking, alcohol, unbalanced diet, lack of exercise.
4. Obesity:
  - Description: Excess fat accumulation, leading to weight gain.
  - Effect: Increases risk of other diseases.
  - Main Causes: Junk food, physical inactivity, stress, hormonal imbalance.
5. Cancer:
  - Description: Uncontrolled cell growth.
  - Main Types: Lung cancer, breast cancer, liver cancer, skin cancer (examples).
  - Main Causes: Smoking, alcohol, irregular lifestyle, pollution, genetic factors (though primarily lifestyle-influenced, genetic predisposition exists).
6. Stroke:
  - Description: Interruption of blood supply to the brain.
  - Main Causes: High blood pressure, smoking, alcohol, stress.
7. Liver Diseases:
  - Example: Liver cirrhosis (often linked to alcohol).
  - Main Causes: Unhealthy diet, excessive alcohol consumption, consumption of toxic substances.
8. Asthma:
  - Description: Inflammation of the respiratory tract causing difficulty breathing.
  - Main Causes: Dust, smoke, allergies, pollution.
9. Mental Disorders:
  - Examples: Depression, anxiety, insomnia.
  - Cause: Mental imbalance.
  - Main Causes: Stress, social pressure, poor lifestyle.
10. Bone Disorders:
  - Examples: Osteoporosis (decreased bone strength), Arthritis (inflammation and pain in joints).
  - Main Causes: Deficiency of calcium and vitamin D, excess weight, lack of exercise.

IV. Prevention and Solutions (Based on provided text - incomplete)

Adopt a healthy diet: Consume green vegetables, fiber, protein, and low-fat foods.
Exercise regularly: (Section cut off in original text)

Ch-11 Human Diseases: Communicable & Non-Communicable Diseases

Diseases can be broadly classified into two main categories:

Communicable Diseases: Diseases that spread from one person to another.
Non-Communicable Diseases: Diseases that are not contagious and do not spread from one person to another.

Communicable Diseases

These diseases are caused by microorganisms (bacteria, viruses, fungi, parasites, etc.) and spread from one person to another through various mediums such as air, water, food, contaminated objects, and vectors.

1. Bacterial Diseases

Bacteria are microorganisms, some of which can cause various diseases in humans. These diseases spread through contaminated water, food, air, vectors, and contact with infected individuals.

(a) Airborne Bacterial Diseases

These diseases spread through sneezing, coughing, or breathing of an infected person.

Disease	Causative Bacteria	Symptoms	Spread	Treatment
Tuberculosis (TB)	Mycobacterium tuberculosis	Persistent cough, blood in sputum, weight loss, fatigue, night sweats, lung infection	Through the air (coughing, sneezing)	BCG vaccine, Antibiotics (Isoniazid, Rifampin)
Diphtheria	Corynebacterium diphtheriae	White membrane in throat, difficulty breathing, fever, weakness	Contact with infected person, Through the air	DPT vaccine, Antibiotics
Whooping Cough/Pertussis	Bordetella pertussis	Persistent severe cough, difficulty breathing	Through the air	DPT vaccine, Antibiotics

(b) Water & Foodborne Bacterial Diseases

These diseases are caused by consuming contaminated water and infected food.

Disease	Causative Bacteria	Symptoms	Spread	Treatment
Cholera	Vibrio cholerae	Diarrhea & vomiting, dehydration, excessive thirst, weakness	Contaminated water and food	ORS, Antibiotics (Tetracycline)
Typhoid Fever	Salmonella typhi	High fever (103-104°F), headache, abdominal pain, diarrhea/constipation	Contaminated water and food	Typhoid vaccine, Antibiotics (Chloramphenicol, Ciprofloxacin)
Food Poisoning	Salmonella, Staphylococcus aureus	Vomiting, diarrhea, abdominal pain, fever, weakness	Contaminated food and water	Adequate fluid intake, Antibiotics

(c) Sexually & Skin Transmitted Bacterial Diseases

Disease	Causative Bacteria	Symptoms	Spread	Treatment
Gonorrhea	Neisseria gonorrhoeae	Burning during urination, abnormal genital discharge	Unsafe sexual practices	Antibiotics (Ceftriaxone)
Syphilis	Treponema pallidum	Sores on genitals, skin, mouth; nervous system effects	Unsafe sex, infected needles	Penicillin antibiotics

(d) Vector-Borne Bacterial Diseases

Disease	Causative Bacteria	Vector	Symptoms	Spread	Treatment
Lyme Disease	Borrelia burgdorferi	Tick bites	Red rash, fever, headache	Through tick bites	Antibiotics (Doxycycline)
Plague	Yersinia pestis	Infected rats, fleas	Fever, chills, swollen lymph nodes	Through vectors	Antibiotics (Streptomycin)

Prevention of Bacterial Diseases

Vaccination: BCG, DPT, typhoid, and cholera vaccines.
Hygiene: Handwashing, consuming clean food and water.
Safe sex: Use condoms.
Vector control: Controlling mosquitoes and rats.
Proper medication: Taking antibiotics as advised by a doctor.

2. Viral Diseases

Viruses are microorganisms that enter living cells, grow, and divide within them, causing various diseases.

(a) Airborne Viral Diseases

These diseases spread through the air from an infected person's sneezing, coughing, or breathing.

Disease	Causative Virus	Symptoms	Spread	Treatment
COVID-19	SARS-CoV-2	Fever, cough, difficulty breathing, loss of taste/smell, fatigue	Air	Vaccines, masks, social distancing
Common Cold	Rhinoviruses, coronaviruses, adenoviruses	Runny nose, cough, sore throat, sneezing	Air, contact with infected person	No specific cure, supportive care, rest
Influenza (Flu)	Influenza Virus	High fever, chills, headache, body aches	Air, contact with infected person	Viral medications (Oseltamivir, Zanamivir)
Measles	Measles Virus	Red rash, fever, cough, eye irritation	Air, contact with infected person	MMR vaccine
Rubella (German Measles)	Rubella Virus	Mild fever, red rash, potential harm to fetus	Air, contact with infected person	MMR vaccine
Smallpox (Eradicated)	Variola Virus	Blisters all over body, fever, weakness	Air, contaminated objects	Eradicated by WHO (1980) due to vaccination

(b) Water and Foodborne Viral Diseases

These diseases are caused by consuming contaminated water and food.

Disease	Causative Virus	Symptoms	Spread	Treatment
Hepatitis A and E	Hepatitis A and E viruses	Jaundice, loss of appetite, fatigue, abdominal pain	Contaminated water and food	Hepatitis A vaccine, Clean water
Rotavirus Infection	Rotavirus	Severe diarrhea, dehydration, vomiting, fever	Contaminated water, contact	Rotavirus vaccine, ORS

(c) Vector-Borne Viral Diseases

These diseases are spread by the bites of mosquitoes, flies, and other insects.

Disease	Causative Virus	Vector	Symptoms	Spread	Treatment
Dengue	Dengue Virus	Aedes mosquito	High fever, decreased platelets, rash, headache	Bite of Aedes mosquito	Fluids, painkillers
Chikungunya	Chikungunya Virus	Aedes mosquito	High fever, joint pain, headache	Bite of Aedes mosquito	Painkillers, rest
Japanese Encephalitis	Japanese Encephalitis Virus	Culex mosquito	Brain swelling, fever, unconsciousness	Bite of Culex mosquito	JE vaccine, supportive care

(d) Sexually and Blood Transmitted Viral Diseases

Disease	Causative Virus	Symptoms	Spread	Treatment
HIV/AIDS	Human Immunodeficiency Virus (HIV)	Weakening of immune system, frequent infections	Unsafe sex, infected blood/needles	Antiretroviral therapy (ART)
Hepatitis B and C	Hepatitis B and C viruses	Liver inflammation, jaundice, fatigue	Infected blood, unsafe sex/needles	Hepatitis B vaccine, Antivirals

Prevention of Viral Diseases

Vaccination: MMR, flu, COVID-19, hepatitis, etc.
Hygiene: Regular hand washing, drinking clean water.
Safe Sex: Use of condoms.
Vector Control: Prevention from mosquito bites.
Preventive Measures: Wearing masks, maintaining distance from infected persons.

3. Fungal Diseases

Fungi are microorganisms that can affect the skin, nails, respiratory system, and internal organs. They spread rapidly in people with moisture, warmth, and a weakened immune system.

(a) Skin and Nail Fungal Diseases

Disease	Causative Fungi	Symptoms	Spread	Treatment
Ringworm (Dermatophytosis)	Trichophyton, Microsporum, Epidermophyton	Circular, red rashes, intense itching/burning	Contaminated clothing, towels, contact	Antifungal cream (Clotrimazole, Miconazole)
Athlete's Foot (Tinea Pedis)	Trichophyton rubrum	Itching, cracks, blisters on feet, nail infection	Wet shoes, pools, contaminated clothing	Antifungal powder/medications
Nail Infection (Onychomycosis)	Trichophyton	Yellowing/browning, thickening/weakening of nails	Contaminated clippers, damp places	Antifungal medications (Terbinafine, Itraconazole)

(b) Oral and Genital Fungal Infections

Disease	Causative Fungi	Symptoms	Spread	Treatment
Oral Thrush	Candida albicans	White coating in mouth, burning, taste change	Weak immunity, excessive antibiotics	Antifungal mouthwash (Nystatin)
Vaginal Yeast Infection	Candida albicans	Itching, burning, white discharge in vagina	Weak immunity, diabetes, contraceptives	Antifungal creams/capsules (Fluconazole)

(c) Systemic Fungal Infections

Disease	Causative Fungi	Symptoms	Spread	Treatment
Aspergillosis	Aspergillus fumigatus	Lung infection, cough, difficulty breathing	Contaminated air, dust, soil	Antifungal medications (Voriconazole)
Histoplasmosis	Histoplasma capsulatum	Fever, fatigue, chest pain	Bird/bat droppings	Antifungal medications (Itraconazole)
Cryptococcosis	Cryptococcus neoformans	Brain swelling, headache, vomiting	Bird droppings, contaminated soil	Antifungal medications (Amphotericin B)
Black Fungus (Mucormycosis)	Mucorales fungi	Fever, chills, headache, weakness, nasal congestion, eye swelling, facial blackening	Weak immune system, uncontrolled diabetes	Amphotericin B injection
Candidemia (Candida Blood Infection)	Candida species	Fever, fatigue, blood infection	Weak immunity, hospitalized patients	Antifungal injections (Echinocandins)

Prevention of Fungal Diseases

Maintain hygiene: Keep skin dry and clean.
Avoid contaminated objects: Do not share shoes, towels, nail cutters.
Maintain strong immunity: Eat a balanced diet, boost immunity.
Avoid overuse of antibiotics as it can increase fungal infections.
Avoid infected places: Do not stay in wet, dirty, and dark places for a long time.

4. Parasitic Diseases

Parasites are microorganisms that live in the body of another organism (host), obtain nutrition, and cause various diseases. They can affect the intestines, blood, skin, and other organs in the human body.

(a) Vector-Borne Parasitic Diseases

These diseases spread through the bites of mosquitoes, flies, lice, and other insects.

Disease	Causative Parasite	Vector	Symptoms	Treatment
Malaria	Plasmodium species (P. falciparum, etc.)	Female Anopheles mosquito	High fever, chills, headache, weakness, anemia	Malaria medications (Chloroquine, Artemisinin)
Kala-azar / Visceral Leishmaniasis	Leishmania donovani	Sandfly	Prolonged fever, darkening of the skin	Antimony compounds, Amphotericin B
Elephantiasis / Lymphatic Filariasis	Wuchereria bancrofti, Brugia malayi	Culex mosquito	Excessive swelling of legs/arms, swollen lymph nodes	Diethylcarbamazine (DEC), Albendazole

(b) Water & Foodborne Parasitic Diseases

These diseases are caused by consuming contaminated water, contaminated food, or undercooked meat.

Disease	Causative Parasite	Symptoms	Treatment
Amoebiasis (Amoebic Dysentery)	Entamoeba histolytica	Bloody diarrhea, abdominal pain, vomiting, liver infection	Metronidazole, Tinidazole
Giardiasis	Giardia lamblia	Watery diarrhea, abdominal cramps, gas, weight loss	Metronidazole, Nitazoxanide
Toxoplasmosis	Toxoplasma gondii	Fever, muscle pain, weight loss, malnutrition	Sulfadiazine, Pyrimethamine

(c) Helminthic Parasitic Diseases (Worms)

These diseases are caused by worm infections that affect the intestines, blood, and other organs.

Disease	Causative Parasite	Symptoms	Treatment
Hookworm Infection	Necator americanus, Ancylostoma duodenale	Anemia, fatigue, abdominal pain, diarrhea	Albendazole, Mebendazole
Ascariasis	Ascaris lumbricoides	Abdominal pain, loss of appetite, diarrhea, vomiting, weight loss	Albendazole, Mebendazole
Tapeworm Infection / Taeniasis	Taenia solium, Taenia saginata	Abdominal pain, loss of appetite	Praziquantel, Niclosamide
Hydatid Disease	Echinococcus granulosus	Liver/lung cysts, abdominal/respiratory problems	Albendazole, surgery

Prevention of Parasitic Diseases

Consume clean water and food: Avoid contaminated water and undercooked food.
Protect yourself from mosquitoes: Use mosquito nets and repellents.
Maintain personal hygiene: Wash hands, keep nails clean.
Avoid contact with contaminated soil: Wear shoes and maintain cleanliness.
Exercise caution with animals: Prevent infections spread by pets and other animals.
Take medication on time: Take anthelmintic drugs (Albendazole) regularly if advised.

Non-Communicable Diseases (NCDs)

These diseases are not caused by any infection, but arise due to lifestyle, genetics, hormonal imbalance, environmental factors, and chronic illnesses.

(a) Genetic Diseases

Genetic diseases are illnesses that are transferred from parents to offspring through DNA or chromosomes. These arise due to mutations in genes or chromosomal abnormalities.

(i) Single Gene Disorders

These diseases are caused by a mutation in a single gene.

Disease	Definition	Cause	Symptoms	Treatment/Management
Hemophilia	Blood does not clot properly	Defective X-linked gene (X-linked Recessive)	Excessive bleeding, joint bleeding/swelling	Factor VIII/IX protein injections
Thalassemia	Decrease in hemoglobin production	Mutation in HBB gene (Autosomal Recessive)	Anemia, bone weakness	Prenatal screening, blood transfusion, bone marrow transplant
Sickle Cell Anemia	RBCs become sickle-shaped, disrupting blood flow	Mutation in HBB gene (Autosomal Recessive)	Fatigue, weakness, difficulty breathing, joint pain	Blood transfusions, Hydroxyurea medication
Huntington's Disease	Degeneration of brain cells	Mutation in HTT gene (Autosomal Dominant)	Memory loss, muscle imbalance, confusion	Symptom control with medications
Color Blindness	Inability to distinguish red/green colors	Defective X-linked gene (X-linked Recessive)	Difficulty identifying red and green	Special glasses can help distinguish colors
Muscular Dystrophy	Progressive muscle weakening and breakdown	Mutation in Dystrophin gene (X-linked)	Muscle weakness, difficulty walking	Physiotherapy, steroids (no complete cure)

(ii) Chromosomal Disorders

These diseases are caused by abnormalities in the number or structure of chromosomes.

Disorder	Definition	Cause	Symptoms	Management/Prevention
Down Syndrome	Extra copy of chromosome 21 (Trisomy 21)	Error in cell division	Intellectual disability, facial features, short stature	Prenatal screening
Turner Syndrome (XO)	Female missing one X chromosome (45, XO)	Absence of X chromosome	Short stature, underdeveloped reproductive organs	Hormone therapy, reproductive medicine
Klinefelter Syndrome (XXY)	Male with extra X chromosome (47, XXY)	Abnormality in chromosome number	Abnormal breast development, reduced fertility	Hormone therapy, physiotherapy

(iii) Metabolic Disorders

These diseases are caused by a deficiency or dysfunction in enzymes affecting metabolic pathways.

Disorder	Definition	Cause	Symptoms	Management
Phenylketonuria (PKU)	Problem breaking down phenylalanine amino acid	Mutation in PAH gene	Intellectual disability, seizures	Special low-phenylalanine diet
Albinism	Lack of melanin pigment	Mutation in Tyrosinase gene	White skin, light hair, sun sensitivity	Sun protection, eye care

Prevention/Management of Genetic Diseases

Genetic Counseling: Genetic testing before conception.
Prenatal Testing: Detecting Down syndrome and other disorders during pregnancy.
Lifestyle Improvements: Balanced diet and a healthy lifestyle can sometimes mitigate symptoms or improve overall health.

(b) Hormonal Disorders

Hormonal disorders arise due to an imbalance (excess or deficiency) of hormones produced by endocrine glands. Hormones regulate body growth, metabolism, reproduction, mental health, and other bodily functions.

Disorder	Definition	Cause	Symptoms	Treatment
Hypothyroidism	Deficiency of thyroxine	Insufficient production of T3, T4	Fatigue, weight gain, cold intolerance, hair loss, dry skin, constipation	Levothyroxine medication, iodine-rich diet
Hyperthyroidism	Excess of thyroxine	Excessive production of T3, T4, Graves' disease	Weight loss, sweating, nervousness, rapid heart rate, insomnia	Anti-thyroid meds, radioactive iodine therapy
Goiter	Enlargement of thyroid	Iodine deficiency, hypo/hyperthyroidism	Swelling in neck, difficulty swallowing/breathing	Iodine-rich diet, surgery

Disorder	Definition	Cause	Symptoms	Treatment
Diabetes Mellitus	Insulin imbalance	Type-1: Pancreas doesn't produce insulin; Type-2: Body can't use insulin properly	Frequent urination, excessive thirst, fatigue, slow wound healing	Type-1: Insulin injections; Type-2: Lifestyle, meds (Metformin)

Disorder	Definition	Cause	Symptoms	Treatment
Cushing's Syndrome	Excess cortisol	Excessive cortisol production	Moon face, obesity, high blood pressure, weak bones	Monitor steroid meds, surgery
Addison's Disease	Deficiency cortisol	Insufficient cortisol production, autoimmune, infections	Fatigue, weakness, low blood pressure, skin darkening	Hydrocortisone therapy

Disorder	Definition	Cause	Symptoms	Treatment
Growth Hormone Excess	Abnormally high GH	Pituitary tumor	Gigantism (childhood), Acromegaly (adults)	Surgery, medications
Growth Hormone Deficiency	Abnormally low GH	Pituitary issue, genetic	Dwarfism (childhood)	Growth hormone injections

(v) Reproductive Hormone Disorders

Disorder	Definition	Cause	Symptoms	Treatment
Polycystic Ovary Syndrome (PCOS)	Excessive male hormones in women	Excessive androgen production	Irregular menstruation, excess facial hair, weight gain, decreased fertility	Hormone therapy, healthy lifestyle
Hypogonadism	Low production of sex hormones (testosterone/estrogen)	Genetic factors, aging, injury	Men: Muscle weakness, low libido; Women: Irregular menstruation, weak bones	Hormone replacement therapy

(vi) Other Hormonal Disorders

Disorder	Definition	Cause	Symptoms	Treatment
Melatonin Imbalance	Sleep disorders	Deficiency/excess of melatonin	Insomnia, sleepiness	Melatonin supplements, sleep schedule

Prevention of Hormonal Disorders

Maintain a balanced diet.
Regular exercise to prevent obesity and diabetes.
Stress management through meditation and yoga.
Regular medical check-ups to monitor hormone levels.
Do not take hormonal medications without consulting a doctor.

(c) Cardiovascular Diseases (CVDs)

CVDs are a group of diseases affecting the heart and blood vessels, caused by unhealthy lifestyles, high blood pressure, high cholesterol, obesity, smoking, and other factors.

Disease	Definition	Cause	Symptoms	Treatment
Coronary Artery Disease (CAD)	Narrowed/blocked coronary arteries	Atherosclerosis, high BP, smoking, obesity	Chest pain (angina), shortness of breath, heart attack risk	Lifestyle changes, meds, angioplasty, bypass
Heart Attack (Myocardial Infarction)	Complete blockage of blood to heart muscle	Blood clots, high BP, smoking, diabetes	Sudden severe chest pain (jaw/arm pain), sweating, weakness	Emergency meds, angioplasty, bypass surgery
Hypertension (High Blood Pressure)	Blood pressure consistently ≥ 140/90 mmHg	Unhealthy lifestyle, salt/fat intake, stress, obesity, inactivity	Headache, dizziness, fatigue, heart attack/stroke risk	Lifestyle improvements, reduced salt, medications
Stroke (Brain Attack)	Interrupted blood supply to the brain (Ischemic or Hemorrhagic)	High blood pressure, artery blockage	Sudden weakness (face, arm, leg), difficulty speaking/seeing	Clot-busting drugs (tPA), BP control
Arrhythmia – Irregular Heartbeat	Heartbeat too fast (Tachycardia) or too slow (Bradycardia)	Electrical signal issues, smoking, caffeine, stress	Abnormal heartbeat sensation, fainting, difficulty breathing	Pacemaker, ICD
Congenital Heart Diseases	Heart structural defects present from birth	Genetic, environmental during development	Difficulty breathing, bluish skin	Surgery, catheter procedures
Cardiac Arrest – Sudden Stoppage	Heart suddenly stops beating	Severe arrhythmia, heart attack	Sudden loss of consciousness, no breathing	CPR, defibrillation

Heart Disease Prevention

Healthy Diet: High fiber, fruits, vegetables; reduce salt and fat.
Regular Exercise: 30-45 minutes daily (walking, yoga, cardio).
Avoid Smoking and Alcohol.
Reduce Stress: Meditation, music, social activities.
Regular Health Checkups: Blood pressure, cholesterol, blood sugar.
Adequate Sleep: 7-8 hours.

Heart Disease Diagnostic Tests

ECG (Electrocardiogram): Records electrical activity.
Echocardiography: Assesses heart structure and function.
Stress Test: Checks heart efficiency under exertion.
Angiography: Checks for coronary artery blockages.
Blood Tests: Cholesterol and sugar levels.

Heart Disease Treatments

Medications: Blood pressure control (Beta-blockers, ACE inhibitors), cholesterol reduction (Statins).
Surgery: Angioplasty (opening blocked arteries), Bypass surgery (re-establishing blood flow).

(d) Cancer

Cancer is a serious disease where body cells divide uncontrollably, forming tumors that can spread (metastasis).

Types of Cancer (by cell type): Carcinoma (epithelial), Sarcoma (bones, muscles), Leukemia (blood), Lymphoma (lymphatic), Myeloma (bone marrow plasma).
Types of Cancer (by affected organ): Lung, Breast, Cervical, Colorectal, Skin, Liver, Brain, etc.

Causes of Cancer

Biological Factors: Genetics, Hormonal Imbalance (breast/uterine).
Environmental Factors: Tobacco/Smoking (lung, throat, mouth, liver), Excessive Alcohol, Pollution/Chemicals (asbestos, arsenic).
Lifestyle Factors: Unhealthy Diet (low fiber, high fat/processed), Physical Inactivity (obesity, diabetes link).
Infectious Causes: Viral Infections (HPV -> Cervical, Hepatitis B/C -> Liver, EBV -> Lymphoma).

Symptoms of Cancer

Tumor or swelling (abnormal lump).
Sudden unexplained weight loss.
Persistent cough (with blood in phlegm).
Excessive fatigue.
Changes in skin (mole changes, non-healing sores).
Loss of appetite, digestive problems.
Blood in stool or urine.

Diagnosis of Cancer

Biopsy: Tissue testing.
Imaging: CT Scan, MRI (stage and spread), X-ray, Ultrasound (lung, breast, etc.), PET Scan (spread).
Blood Test (Tumor Markers): Identifying cancer cells in blood.

Treatment of Cancer

Surgery: Remove affected tissue/organ (e.g., Mastectomy, Gastrectomy).
Chemotherapy: Using drugs to destroy cancer cells (side effects: hair loss, weakness, nausea).
Radiation Therapy: High-energy radiation to destroy cells (skin, brain, prostate).
Immunotherapy: Strengthening the immune system.
Hormone Therapy: For hormone-sensitive cancers (breast, prostate).

Prevention of Cancer

Avoid smoking and alcohol.
Eat a balanced diet: Fiber, vegetables, fruits, antioxidants.
Regular exercise.
Prevent infections: Vaccination for HPV and Hepatitis B.
Regular medical checkups.

(e) Neurological Disorders

Neurological disorders affect the brain, spinal cord, and nerves, caused by genetic factors, infections, injury, nutritional deficiencies, autoimmune disorders, etc.

(i) Neurodegenerative Diseases

Caused by gradual destruction of brain and nerve cells.

Disease	Definition	Cause	Symptoms	Treatment/Management
Alzheimer's Disease	Brain cell degeneration, memory loss	Beta-amyloid protein, genetics, age	Memory loss, confusion, mental disorders	Physical therapy, symptom control meds
Parkinson's Disease	Lack of dopamine in the brain	Degeneration of Substantia Nigra, genetics, environment	Tremors, slow movement (bradykinesia)	L-Dopa, Dopamine Agonists
Huntington's Disease	Genetic, gradual brain cell death	Mutation in HTT gene	Memory loss, confusion, uncontrolled movements (chorea)	Symptom control with medications

(ii) Autoimmune Neurological Disorders

Immune system attacks healthy nerve cells.

Disorder	Definition	Cause	Symptoms	Treatment
Multiple Sclerosis (MS)	Immune system attacks myelin, damaging nerves	Genetics, environmental factors	Muscle weakness, balance problems, vision/memory impairment	Symptom control medications
Myasthenia Gravis	Affected communication between muscles/nerves	Immune system attacks acetylcholine receptors	Drooping eyelids, muscle weakness, difficulty speaking/chewing/breathing	Cholinesterase inhibitors, immunotherapy

(iii) Infectious Neurological Diseases

Caused by infections.

Disease	Definition	Cause	Symptoms	Treatment
Meningitis	Infection of membranes around brain/spinal cord	Bacteria (Neisseria meningitidis), Viruses	High fever, headache, neck stiffness, vomiting, seizures	Antibiotics (bacterial), Vaccination (Hib, Meningococcal)
Encephalitis	Infection causing brain inflammation	Viruses (Herpes simplex, JE virus)	Fever, loss of consciousness, seizures	Antiviral drugs (Acyclovir)

(iv) Peripheral Neuropathy Disorders

Affect the spinal cord and peripheral nerves.

Disorder	Definition	Cause	Symptoms	Treatment
Guillain-Barré Syndrome (GBS)	Immune system attacks peripheral nerves	Viral/bacterial infection (Campylobacter jejuni)	Weakness starting in feet, spreading	Plasmapheresis, Immunoglobulin therapy (IVIG)

(v) Other Neurological Disorders

Disorder	Definition	Cause	Symptoms	Treatment
Epilepsy (Seizure Disorder)	Recurring seizures (abnormal brain electrical activity)	Head injury, genetics, brain infections	Convulsions, loss of consciousness, limb stiffness	Anti-epileptic drugs (AEDs), neurosurgery
Spinal Cord Injury	Injury to the spinal cord	Accidents, falls, sports injuries	Paralysis, pain, decreased sensation	Physiotherapy, spinal surgery

Prevention of Neurological Disorders

Maintain a healthy diet: Omega-3 fatty acids, Vitamin B12.
Manage stress: Yoga, meditation, regular exercise.
Vaccination: For Meningitis, Encephalitis, Japanese Encephalitis.
Avoid head injuries: Wear helmets, exercise caution.
Get regular health checkups: For early detection.

(f) Mental Disorders

Mental disorders affect brain function, emotions, thinking, understanding, behavior, and social functioning, impacting daily life and relationships.

(i) Mood Disorders

Affect emotions and mood.

Disorder	Definition	Cause	Symptoms	Treatment
Depression	Persistent sadness, negative thoughts, loss of interest	Biological (serotonin/dopamine deficiency), stress, family history	Excessive sadness, suicidal thoughts, fatigue, appetite changes	Antidepressants (Fluoxetine, Sertraline), Psychotherapy (CBT)
Bipolar Disorder	Shifts between extreme enthusiasm (mania) and sadness (depression)	Biological, genetic, neurotransmitter imbalance	Extreme energy, lack of sleep, sudden mood swings	Mood stabilizers (Lithium, Valproate)

(ii) Anxiety Disorders

Associated with excessive fear, nervousness, and stress.

Disorder	Definition	Cause	Symptoms	Treatment
Generalized Anxiety Disorder (GAD)	Excessive anxiety and nervousness	Genetics, neurotransmitter imbalance	Constant worry, headaches, sweating, increased heart rate	Anti-anxiety meds (Benzodiazepines, SSRIs), Relaxation therapy
Panic Disorder	Sudden attacks of intense nervousness	(Often unclear)	Rapid heartbeat, difficulty breathing, fainting	Antidepressants, breathing techniques
Social Anxiety Disorder	Fear of public speaking/social activities	(Often unclear)	Shyness, self-doubt, sweating	Behavioral therapy, exposure therapy

(iii) Psychotic Disorders

Affect understanding of reality.

Disorder	Definition	Cause	Symptoms	Treatment
Schizophrenia	Loss of touch with reality, delusions/hallucinations	Genetics, neurotransmitter imbalance	Delusions, hallucinations, disorganized thought/speech	Antipsychotic medications

(iv) Personality Disorders

Affect behavior and way of thinking.

Disorder	Symptoms	Treatment
Borderline Personality Disorder (BPD)	Intense emotional swings, self-harming tendencies	DBT (Dialectical Behavior Therapy), therapy
Narcissistic Personality Disorder (NPD)	Self-centeredness, disregard for others, lack of empathy	Psychotherapy, behavioral therapy

Disorder	Definition	Cause	Symptoms	Treatment
Post-traumatic Stress Disorder (PTSD)	Stress/fear persist after traumatic event	Accidents, abuse, war	Flashbacks, nightmares, irritability	CBT, EMDR therapy, antidepressants

(vi) Eating Disorders

Related to food and body image.

Disorder	Definition	Symptoms	Treatment
Anorexia Nervosa	Eating very little, perceiving self as overweight	Rapid weight loss, weakness	Nutritional therapy, psychotherapy
Bulimia Nervosa	Inducing vomiting after excessive eating	(Not listed in source)	Psychotherapy, dietary management

(vii) Childhood & Developmental Disorders

Disorder	Definition	Symptoms	Treatment
Attention Deficit Hyperactivity Disorder (ADHD)	Excessive activity, difficulty concentrating	Lack of attention, hyperactivity, impulsivity	Methylphenidate (Ritalin), behavioral therapy
Autism Spectrum Disorder (ASD)	Difficulty in social interaction/communication	Repetitive actions, lack of social skills	Behavioral therapy, special education

Prevention and Management of Mental Disorders

Pay attention to mental health: Yoga, meditation, stress management.
Adopt a healthy routine: Balanced diet, regular exercise.
Develop positive thinking: Join self-help groups.
Use psychotherapy and medications correctly: Do not discontinue medications without consulting a doctor.
Spread awareness: Do not discriminate against people with mental illness.

(g) Bone Disorders

Bone disorders affect the structure, density, strength, and function of bones, caused by genetics, hormonal imbalances, nutritional deficiencies, infections, injuries, and age.

(i) Bone Density Disorders

Disorder	Definition	Cause	Symptoms	Treatment
Osteoporosis	Weak, brittle bones, fracture risk	Calcium/Vit D deficiency, aging, estrogen deficiency, inactivity, smoking/alcohol	Back pain, spinal curvature, bone pain, easy fractures	Calcium/Vit D supplements, exercise, bisphosphonates
Osteomalacia / Rickets	Softening of bones (adults)/bone deformity (children)	Deficiency of Vit D, phosphorus, calcium; less sun exposure	Bone pain, muscle weakness, bone deformities	Calcium and Vitamin D supplements

(ii) Bone Infection & Inflammation Disorders

Disorder	Definition	Cause	Symptoms	Treatment
Osteomyelitis	Infection of bone/bone marrow	Bacterial (Staphylococcus aureus)/fungal infection, injury, surgery	High fever, swelling/pain, redness, pus formation	Antibiotics (IV), surgical removal
Paget's Disease of Bone	Abnormal, excessive bone growth	Genetics, viral infection	Bone pain, deformities, joint stiffness	Bisphosphonates, physiotherapy

(iii) Bone Deformities & Structural Disorders

Disorder	Definition	Cause	Symptoms	Treatment
Scoliosis	Abnormal spinal curvature	Genetics, congenital defects	Back pain, weak muscles, leg bowing	Back brace, physiotherapy, surgery
Spondylitis	Inflammation of spine/joints	Genetic changes, autoimmune	Bone pain, swelling, weakness	NSAIDs, exercise, physiotherapy

(iv) Bone & Joint Disorders

Disorder	Definition	Cause	Symptoms	Treatment
Osteoarthritis	Wear of joint cartilage	Age, obesity, excessive exertion	Joint pain, stiffness, difficulty walking	Pain relievers, exercise, weight management
Rheumatoid Arthritis (RA)	Autoimmune attack on joint cartilage/bones	Autoimmune disease, heredity	Joint swelling, stiffness, fever	DMARDs, physiotherapy, yoga

(v) Bone Cancer & Tumors

Disorder	Definition	Cause	Symptoms	Treatment
Osteosarcoma	Uncontrolled growth of bone cells	Genetic changes, radiation	Uneven shoulders, back pain, stooping posture	Chemotherapy, radiation, surgery (grafting)

Prevention and Treatment of Bone Disorders

Dietary and Nutritional Improvements:
- Consume calcium-rich foods (milk, yogurt, cheese, leafy greens).
- Obtain Vitamin D (sun exposure, eggs, fish).
- Consume magnesium and phosphorus (nuts, seeds, whole grains).
Maintain Physical Activity:
- Exercise (weight training, yoga, swimming).
- Avoid excessive physical stress.
Lifestyle Improvements:
- Avoid smoking and alcohol.
- Maintain correct posture.
- Get regular bone checkups (DEXA scans).

Ch-12 Endemic, Epidemic, and Pandemic Diseases - Diagnosis and Control

Introduction: Infectious diseases are categorized based on how widely and frequently they spread within populations and geographic areas. These categories help public health officials understand and respond to outbreaks.

1. Classification of Infectious Diseases

Infectious diseases are typically classified into three main categories:

1.1 Endemic Diseases

Definition: Diseases that are constantly present within a particular area, population, or community at an expected level. They are common in that area and occur regularly, but do not typically spread on a large, uncontrolled scale.
Examples: Malaria, Dengue, Kala-azar, Filariasis (often specific to certain tropical or subtropical regions).
Diagnosis:
- Blood tests (e.g., Malaria Antigen Test, Dengue NS1 Test, ELISA)
- Identification of patient symptoms.
Control:
- Mosquito control (e.g., mosquito nets, insecticides)
- Vaccination and medications (e.g., Chloroquine, Artemisinin-based therapy for malaria)
- Sanitation campaigns (e.g., preventing waterlogging, cleaning drains to eliminate breeding sites).

1.2 Epidemic Diseases

Definition: Diseases that suddenly spread in an area, country, or population and affect a significantly larger number of people than is usual or expected for that area within a specific time frame. The increase in cases is rapid.
Examples: Spanish Flu (1918), Swine Flu (H1N1 – 2009), Ebola (2014 outbreak in West Africa), Chikungunya.
Diagnosis:
- PCR test
- Blood test
- Study of patient symptoms.
Control:
- Isolation of infected individuals
- Vaccination and medications (e.g., Tamiflu for swine flu)
- Travel restrictions and awareness campaigns
- Improvement and monitoring of health services.

1.3 Pandemic Diseases

Definition: An infectious disease that has spread across multiple countries or continents, usually affecting a large number of people globally. It is a widespread and serious level of infection.
Examples: COVID-19 (2019-2023), Black Death (1347-1351), Asian Flu (1957), HIV/AIDS (1981 to present).
Diagnosis:
- RT-PCR test
- Serology test.
Control: (Often involves a combination of measures specific to the pathogen, similar to epidemic control but on a global scale. See COVID-19 control measures below as a prime example).

2. Difference between Endemic, Epidemic, and Pandemic

These terms describe the level and spread of a disease:

Endemic: Constantly present at an expected level in a specific region. (Example: Malaria in tropical regions).
Epidemic: A sudden, rapid increase in cases above the expected level within a particular region or country. (Example: Ebola outbreak in West Africa).
Pandemic: Global spread of a new disease affecting a large number of people across many countries/continents. (Example: COVID-19 worldwide).

3. Case Study: COVID-19 (A Recent Pandemic)

What is COVID-19? COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. This virus was first identified in Wuhan, China, in December 2019 and subsequently spread globally.

Why did COVID-19 become a pandemic? The World Health Organization (WHO) declared COVID-19 a pandemic on March 11, 2020, because:

It was spreading rapidly across the globe.
It had reached almost all countries worldwide.
It had a severe impact, causing millions of deaths and overwhelming healthcare systems.

Main Symptoms of COVID-19:

Fever
Cough
Difficulty breathing
Sore throat
Loss of taste and smell
Fatigue
In some cases, stomach problems and skin rashes

How it Spreads:

Through respiratory droplets released when an infected person coughs, sneezes, or talks.
By touching a contaminated surface and then touching the mouth, nose, or eyes.
Through airborne transmission (especially in poorly ventilated, crowded indoor spaces).

Prevention Measures (Specific to COVID-19):

Wearing masks
Frequent hand washing (for at least 20 seconds)
Avoiding crowded places
Getting vaccinated
Maintaining physical distance

Vaccination and Treatment:

Vaccination: Several vaccines were developed (e.g., Covaxin, Covishield, Pfizer, Moderna, Sputnik V) to reduce severe illness and transmission.
Treatment: Involved supportive care, oxygen therapy, and specific antiviral drugs for eligible patients.

Control Measures (Specific to COVID-19 Pandemic):

Global lockdowns and travel restrictions
Tracing and testing of infected individuals
Social distancing and mask-wearing mandates
Increased ICU facilities and treatment of patients
Monitoring and guidance by international health organizations (WHO, CDC).

Impact and Changes Due to COVID-19:

Significant disruption to economic activities due to restrictions.
Widespread adoption of remote work and online education.
Increased focus on and investment in strengthening global health systems.

4. General Prevention and Control of Infectious Diseases

Controlling the spread of infectious diseases requires efforts at multiple levels:

4.1 Individual Level Prevention:

Get Vaccinated: Stay up-to-date with recommended vaccinations (e.g., for preventable diseases like polio, measles, and relevant regional diseases like malaria, dengue, or pandemic-specific vaccines like COVID-19).
Maintain Hygiene: Practice good personal hygiene, including regular handwashing (especially before eating and after using the restroom or being in public places), wearing masks when appropriate (during outbreaks or in crowded settings), and practicing respiratory etiquette (covering coughs/sneezes).
Adopt a Healthy Lifestyle: A balanced diet, regular exercise, adequate sleep, and managing stress can boost the immune system.
Mosquito Control: Prevent mosquito breeding (e.g., by eliminating standing water sources) and use protection (e.g., mosquito nets, repellents) in areas where mosquito-borne diseases are endemic or epidemic.

4.2 Community and Government Efforts:

Improve Infrastructure: Invest in and maintain safe water and sewage systems.
Increase Surveillance: Establish robust systems for tracking, testing, and monitoring infectious diseases.
Implement Regulations: Enforce travel and trade regulations when necessary to limit disease spread during outbreaks.
Educate the Public: Conduct health programs and use media campaigns to raise awareness about disease prevention, symptoms, and recommended actions.

4.3 Global Level Control:

Follow Guidelines: Adhere to recommendations and guidelines issued by international health organizations like the WHO and CDC.
Collaborate: Foster international cooperation and collaboration between countries, the United Nations (UN), and other global health bodies.
Invest in Research: Fund and conduct research into new viruses, bacteria, and effective treatments and vaccines to prepare for future threats.

Ch-13 Immunization and Vaccination

Introduction: Immunization and vaccination are crucial processes that strengthen the body's immune system to prevent infectious diseases. They play a vital role in controlling infections and preventing outbreaks, including epidemics and pandemics.

1. What is Immunization?

Immunization is a biological process by which the immune system is trained to develop the ability to fight specific infections. This training can occur naturally or through artificial means.

Types of Immunization:

Active Immunization: This occurs when the body's own immune system is stimulated to produce antibodies and immune cells in response to a pathogen or vaccine.
- Examples: Immunity developed after natural infection with a disease, or immunity achieved through vaccination.
Passive Immunization: This involves receiving pre-formed antibodies from another source. The body does not produce these antibodies itself, so the immunity is temporary.
- Examples: Antibodies transferred from a mother to her child through the placenta or breast milk, or the injection of antiserum containing antibodies.

2. What is Vaccination?

Vaccination is the specific process of introducing a weakened, inactive, or partial form of a pathogen (or its toxins) into the body to deliberately train the immune system against that particular disease.

What is a Vaccine?

A vaccine is the substance used in vaccination. It is a biological preparation containing weakened or inactive disease-causing microorganisms, their toxins, or specific parts of them. When administered, a vaccine triggers an immune response without causing the full disease, preparing the body to fight off future infections by the actual pathogen.

Types of Vaccines:

Live Attenuated Vaccines: Contain weakened (attenuated) living germs. They produce a strong, long-lasting immune response.
- Examples: BCG (Tuberculosis), MMR (Measles, Mumps, Rubella), Oral Polio Vaccine (OPV).
Inactivated Vaccines (Killed Vaccines): Contain germs that have been killed by heat or chemicals. They usually require multiple doses to build immunity.
- Examples: Inactivated Polio Vaccine (IPV), Rabies vaccine.
Toxoid Vaccines: Made from inactivated toxins produced by bacteria. They train the body to fight the toxin, not the bacteria itself.
- Examples: Tetanus, Diphtheria vaccine.
Subunit, Recombinant, Conjugate Vaccines: These vaccines contain only specific parts of the germ (like proteins or polysaccharides) that trigger an immune response.
- Examples: Hepatitis B vaccine, HPV (Human Papillomavirus) vaccine.
mRNA Vaccines: Contain messenger RNA (mRNA) that instructs the body's cells to make a specific protein from the virus (e.g., the spike protein of SARS-CoV-2). This protein then triggers an immune response.
- Examples: Pfizer-BioNTech and Moderna vaccines for COVID-19.

3. Importance of Vaccination

Vaccination is a cornerstone of public health due to its numerous benefits:

Prevention of infectious diseases: It has led to the control or near-eradication of diseases like smallpox, polio, measles, and diphtheria.
Herd Immunity (Community Immunity): When a large percentage of a population is vaccinated, it reduces the spread of disease, providing protection even to those who cannot be vaccinated (like infants, the elderly, or immunocompromised individuals).
Prevention of Epidemics and Pandemics: High vaccination rates help contain outbreaks and prevent them from escalating into widespread epidemics or pandemics.
Protection of children and vulnerable people: Vaccines are particularly important for protecting young children, the elderly, and individuals with weak immune systems who are most susceptible to severe illness.
Reducing the burden on the healthcare system: By preventing illness, vaccination significantly decreases hospital admissions and the overall strain on healthcare resources.

4. Immunization Programs

Immunization programs are organized efforts by governments and international bodies to deliver vaccines to target populations.

4.1 National Programs (Example: India's Universal Immunization Program - UIP)

About UIP: The UIP is one of the largest public health programs globally, launched by the Indian government in 1985. It aims to provide free vaccination against deadly diseases to infants, children, and pregnant women throughout the country.
Vaccines and Diseases Covered Under UIP:

Vaccine Name	Diseases Protected	Typical Schedule
BCG	Tuberculosis (TB)	At birth (1 dose)
Hepatitis B	Hepatitis B infection	At birth and subsequent doses
Oral Polio Vaccine (OPV)	Polio	At birth, 6, 10, and 14 weeks; booster dose
Inactivated Polio Vaccine (IPV)	Polio	6 and 14 weeks (fractional dose)
DPT	Diphtheria, Tetanus, Pertussis	6, 10, 14 weeks and 16-24 months (boosters)
Pentavalent Vaccine	Diphtheria, Tetanus, Pertussis, Hepatitis B, Hib	6, 10, and 14 weeks
Rotavirus Vaccine	Rotavirus Diarrhea	6, 10, 14 weeks
Pneumococcal Conjugate Vaccine (PCV)	Pneumonia	6 weeks, 14 weeks, and 9-12 months
MR Vaccine	Measles and Rubella	9-12 months and 16-24 months
JE Vaccine	Japanese Encephalitis (JE)	9-12 months and 16-24 months (in affected areas)
Tetanus and Diphtheria (Td) Vaccine	Tetanus and Diphtheria (for older children/adolescents)	10 years and 16 years

Goals and Objectives of UIP:
- Protect children and pregnant women from major vaccine-preventable diseases.
- Increase vaccination coverage to reach all eligible individuals with free vaccines.
- Prevent disease transmission and contribute to national elimination/eradication targets for specific diseases.
- Improve public health standards through the inclusion of safe and effective vaccines.
Special Programs Associated with UIP:
- Mission Indradhanush (2014): An initiative launched to accelerate the coverage of immunization to cover partially vaccinated and unvaccinated children and pregnant women, aiming for 90% full immunization coverage.
- Intensified Mission Indradhanush (IMI) (2017, 2019, 2021, etc.): Subsequent campaigns designed as special drives to further improve vaccination coverage in difficult-to-reach areas and populations.
Achievements and Challenges of UIP:
- Achievements: India has successfully eradicated Polio. Significant progress has been made towards Measles and Rubella elimination. The program provides vaccines against 12+ diseases.
- Challenges: Limited access to vaccination services in some remote and rural areas. Vaccine hesitancy and lack of awareness among certain populations. Logistical challenges related to vaccine storage ("cold chain") and delivery.

4.2 Global Programs

Expanded Programme on Immunization (EPI): Launched by the World Health Organization (WHO) in 1974 to ensure universal access to vaccines against six major diseases (later expanded). Many national programs like India's UIP are based on the EPI framework.
GAVI, the Vaccine Alliance: A global health partnership (involving WHO, UNICEF, World Bank, Bill & Melinda Gates Foundation, etc.) that works to ensure equitable access to vaccines in lower-income countries.

5. Side Effects of Vaccination

Vaccines are rigorously tested for safety. While generally safe, side effects can occur:

Mild Symptoms: These are common and usually resolve on their own within a few days. Examples include mild fever, soreness, redness, or swelling at the injection site.
Serious Reactions: Very rare but possible. The most severe is a severe allergic reaction (anaphylaxis). Healthcare providers are trained to manage these.
Specific Vaccine Side Effects: Some vaccines may have unique, usually mild, side effects. Examples include a mild rash from the MMR vaccine or a small, temporary lump after the BCG vaccine.

Ch-14 Drugs and Alcohol

Introduction: Substance abuse refers to the harmful use of psychoactive substances, including illicit drugs and alcohol. It is a significant problem affecting individuals, families, and society, often with severe immediate and long-term consequences.

1. Types of Commonly Abused Substances

Different substances affect the body and brain in various ways. Some common categories include:

Cannabinoids:
- Derived from the Cannabis sativa plant.
- Include substances like marijuana, hashish, charas, and ganja.
- Typically administered through inhalation (smoking) or oral ingestion.
- Can affect the cardiovascular system.
- Sometimes misused by athletes.
Coca Alkaloids (Example: Cocaine):
- Derived from the coca plant (Erythroxylum coca), primarily found in South America.
- Interferes with the transport of the neurotransmitter dopamine in the brain.
- Often administered by snorting.
- Acts as a stimulant on the central nervous system, causing intense euphoria and increased energy.
- High doses can induce hallucinations.
Other Abused Drugs:
- Includes misuse of prescription and over-the-counter drugs like barbiturates, amphetamines, and benzodiazepines.
- Misuse of hallucinogens like LSD.
- Morphine, a potent painkiller and sedative derived from opium, is legitimately used in medicine (e.g., post-surgery) but is also highly addictive and subject to abuse.
- Smoking and tobacco use are also forms of substance abuse, involving addiction to nicotine.

2. Effects of Drug and Alcohol Misuse

Substance abuse leads to a wide range of harmful effects, impacting physical health, mental state, and social life.

2.1 General Effects

Immediate Effects: Can include reckless behavior, violence, and vandalism. Acute overdose is a serious risk, potentially leading to coma and death.
Long-Term Effects: Decline in academic or work performance, increased absenteeism, neglect of personal hygiene, feelings of loneliness, depression, isolation from family and friends, irritability, and significant changes in sleep and eating habits.

Addiction can lead to involvement in theft, crime, and social rejection from peers, family, and society.
The entire family is often affected mentally and financially by a member's substance abuse.

2.3 Specific Health Risks

Individuals who inject drugs are at significantly higher risk of contracting blood-borne diseases like HIV/AIDS and Hepatitis B due to sharing needles.
Chronic alcohol and drug use can cause severe organ damage, such as liver cirrhosis and damage to the nervous system.

2.4 Effects During Pregnancy

Alcohol and drug use during pregnancy have severe negative impacts on the developing fetus, leading to birth defects, developmental problems, and long-term health issues for the child.

2.5 Specific Physiological Effects by Gender and Age (Often associated with certain drug types like anabolic steroids)

Effects on Women: Masculinization (development of male characteristics), increased aggression, depression, menstrual irregularities, increased facial and body hair, deepening of the voice.
Effects on Men: Acne, aggression, depression, decreased testicle size, reduced sperm production, baldness.
Effects on Adolescents: Acne, abnormal body development, and stunted bone growth.

3. Substance Abuse in Specific Contexts

Drug Abuse in Sports: Some athletes misuse drugs (including narcotic analgesics, anabolic steroids, diuretics, and hormones) to illegally enhance their physical strength and performance, often referred to as doping.

4. Prevention and Control of Substance Abuse

Preventing substance abuse, particularly among young people, is crucial as addiction can develop quickly, especially during adolescence. "Prevention is better than cure" is highly applicable here.

Key Strategies:

Preventing Excessive Pressure: Encourage children and adolescents to pursue their interests and abilities without facing undue pressure or intense, unhealthy competition that might lead them to seek escape or performance enhancement through substances.
Education and Counseling: Educate young people about the risks and consequences of drug and alcohol abuse. Teach them healthy coping mechanisms and decision-making skills to navigate challenging situations without resorting to substances. Promote engagement in positive activities like sports, music, yoga, and hobbies.
Support from Parents and Friends: Creating a supportive environment where individuals feel comfortable discussing problems with parents or close friends is essential. Providing a safe platform for expressing emotions can help prevent substance abuse as a coping mechanism.
Recognizing Warning Signs: Parents, teachers, and guardians should be vigilant for changes in behavior, academic performance, physical appearance, or social interactions that might indicate substance abuse. Taking appropriate action early is critical.
Professional and Medical Help: Seeking professional help is vital for individuals struggling with or at risk of addiction. This includes consulting psychologists and psychiatrists and utilizing specialized de-addiction and rehabilitation programs.

Substance abuse is a serious public health issue. Proper education, increased awareness, open communication, and timely intervention are the most effective ways to prevent it and help those affected. Staying away from drugs and alcohol is the best path to leading a healthy and happy life.

Ch-15 Plant Parts and Their Functions, Plant Nutrition

Plants are fundamental to life on Earth, providing essential resources like food and oxygen. Understanding their structure and how they function reveals the complexity and importance of these organisms. Different parts of a plant perform various essential functions that contribute to its survival, growth, and reproduction.

1. Main Parts of a Typical Plant

A typical flowering plant is composed of several primary parts, each with distinct roles:

Roots: The underground part, primarily for anchorage and absorption.
Stem: The aerial part, supporting leaves, flowers, and fruits and transporting substances.
Leaves: Typically flat, green structures attached to the stem, primarily for photosynthesis.
Flower: The reproductive structure of angiosperms.
Fruit: Develops from the flower's ovary after fertilization, enclosing the seeds.
Seed: Develops from the ovule, containing the embryo for a new plant.

These parts are interconnected by a Vascular System (Xylem and Phloem) that transports water, minerals, and food throughout the plant.

2. Functions of Plant Parts

Each part of the plant performs specific vital functions:

A. Roots

The root system is typically underground and serves multiple crucial functions:

Anchorage and Support: Roots anchor the plant firmly in the soil, providing mechanical support. Adventitious roots can also provide support (e.g., prop roots, stilt roots).
Absorption: Primary function is the absorption of water and mineral salts from the soil. Root hairs, specialized epidermal extensions, are the main absorptive structures.
Transport: Roots contain vascular tissues (xylem) to transport absorbed water and minerals upwards to the stem and leaves.
Storage: Some roots are modified to store food reserves (e.g., carrot, radish, turnip).
Respiration: In specific environments like marshy areas, modified roots called pneumatophores aid in gas exchange.
Other Modifications: Adventitious roots can also be modified for climbing (e.g., in betel).
Soil Stabilization: Roots help prevent soil erosion by holding soil particles together.

B. Stem

The stem is the main axis of the plant, usually growing above ground:

Support: Provides structural support, holding leaves, flowers, and fruits upright and orienting leaves to maximize sunlight exposure.
Transport: Contains vascular tissues for:
- Upward transport of water and minerals from roots to leaves (via xylem).
- Transport of manufactured food (sugars from photosynthesis) from leaves to other parts (via phloem), which can be upward or downward.
Storage: Stems can be modified for food storage (e.g., underground stems like tubers, rhizomes, corms, bulbs).
Vegetative Propagation: Sub-aerial stem modifications (runners, stolons, offsets, suckers) are involved in asexual reproduction.
Protection: Axillary buds can modify into thorns for defense.
Climbing: Stems can develop tendrils or hooks for climbing.
Photosynthesis: In some plants (e.g., Opuntia), the stem is modified into a green, flattened or cylindrical structure (phylloclade, cladode) to carry out photosynthesis and store water.

C. Leaves

Leaves are typically flat, green appendages, the primary photosynthetic organs:

Photosynthesis: The main function is producing food (sugars) using sunlight, water, and carbon dioxide, facilitated by chlorophyll.
Gas Exchange: Facilitate the exchange of carbon dioxide (for photosynthesis) and oxygen (for respiration) through stomata, small pores on the leaf surface.
Transpiration: Loss of water vapor through stomata. This process helps in the upward movement of water (ascent of sap) and cools the leaf surface.
Guttation: Exudation of excess water in liquid form from leaf margins through hydathodes, particularly in humid conditions.
Modifications: Leaves can be modified for various functions:
- Storage (food and water).
- Climbing (leaf tendrils).
- Protection (spines).
- Trapping insects (in insectivorous plants).
- Photosynthesis (phyllodes, where the petiole becomes leaf-like).

D. Flower

Flowers are the specialized structures for sexual reproduction in angiosperms:

Reproduction: Contain the male and female germ cells required for sexual reproduction.
Attraction: Often brightly colored petals attract pollinators (insects, birds, etc.).
Structure: Typically composed of four whorls:
- Sepals (Calyx): Outermost whorl, usually green, protects the flower in the bud stage.
- Petals (Corolla): Often colorful, attracts pollinators.
- Stamens (Androecium): Male reproductive parts, produce pollen grains in the anthers.
- Carpels/Pistil (Gynoecium): Female reproductive part(s), consisting of stigma (receives pollen), style (stalk), and ovary (contains ovules).
Pollination: Essential for fertilization, involving the transfer of pollen from stamen to stigma.

E. Fruit

A fruit develops from the flower's ovary after fertilization:

Protection: Protects the enclosed seeds from damage.
Seed Dispersal: Plays a crucial role in dispersing seeds away from the parent plant through various mechanisms (e.g., edible fruits attracting animals).

F. Seed

A seed develops from the ovule after fertilization:

Propagation: Contains the embryo, the rudimentary beginning of a new plant.
Protection: The seed coat protects the embryo from dehydration and mechanical damage.
Nourishment: Contains stored food reserves (in cotyledons or endosperm) to nourish the embryo during germination.
Dispersal and Storage: Seeds can be stored, transported, and dispersed, allowing the plant to colonize new areas.
Germination: Under suitable conditions, the embryo germinates and grows into a seedling.

G. Vascular Tissues (Xylem and Phloem)

These are complex tissues forming the plant's internal transport system, extending through roots, stems, and leaves in vascular bundles:

Xylem: Primarily responsible for the upward transport of water and dissolved mineral salts from the roots to all aerial parts. Composed of tracheids, vessels, xylem parenchyma, and xylem fibers.
Phloem: Responsible for the translocation (transport) of sugars (food produced during photosynthesis) and other organic solutes from the leaves (source) to other parts of the plant (sinks) for use or storage. Phloem allows for movement of materials in both upward and downward directions. Composed of sieve tubes, companion cells, phloem fibers, and phloem parenchyma.

These various parts and their specialized functions work in a coordinated manner to ensure the survival, growth, reproduction, and dispersal of plants, highlighting their complexity and ecological importance.

Plant Nutrition: How Plants Obtain and Utilize Nutrients

Plant nutrition is the process by which plants acquire and use the substances necessary for growth, development, and survival. Plants are primarily unique in their ability to produce their own food.

1. Modes of Nutrition in Plants

Plants exhibit two main modes of nutrition:

Autotrophic Nutrition:
- The primary mode for most plants.
- Plants (autotrophs) synthesize their own food (glucose) from simple inorganic substances (carbon dioxide, water, minerals) using an external energy source.
- Key Characteristics: Typically green, contain chlorophyll, use sunlight for energy, produce food via photosynthesis, release oxygen as a byproduct.
Heterotrophic Nutrition:
- Plants that cannot produce all their food or supplement their nutrition by depending on other organisms or decaying organic matter.
- Less common in the plant kingdom, often representing adaptations to nutrient-poor environments.

2. Autotrophic Nutrition: Photosynthesis - The Food-Making Process

Photosynthesis is the core process of autotrophic nutrition in green plants, algae, and some bacteria.

Definition: A biochemical process where light energy is used to synthesize glucose and oxygen from carbon dioxide and water.
General Equation: 6CO₂ + 6H₂O + Light Energy + Chlorophyll → C₆H₁₂O₆ + 6O₂
Components and Products:
- Raw Materials:
  - Carbon Dioxide (CO₂): Absorbed from the atmosphere via stomata (pores, mainly on leaves, regulated by guard cells).
  - Water (H₂O): Absorbed from the soil by roots.
  - Sunlight: Provides the necessary energy.
  - Chlorophyll: Green pigment (located in chloroplasts) that captures light energy.
- Products:
  - Glucose (C₆H₁₂O₆): A carbohydrate, the plant's primary energy source and building block.
  - Oxygen (O₂): Released into the atmosphere via stomata as a byproduct.
Importance of Photosynthesis:
- Produces most of the Earth's oxygen.
- Forms the base of almost all food chains.
- Removes CO₂ from the atmosphere, helping climate regulation.
- Converts solar energy into chemical energy.
- Crucial for carbon and oxygen cycling.
Stages of Photosynthesis: Occurs in chloroplasts (within thylakoid membranes and stroma).
- A) Light-Dependent Reactions (Light Reaction):
  - Location: Thylakoid membranes.
  - Requires light.
  - Light energy is converted to chemical energy (ATP and NADPH).
  - Water is split (photolysis), releasing oxygen.
- B) Light-Independent Reactions (Dark Reaction / Calvin Cycle):
  - Location: Stroma.
  - Does not directly require light, but uses ATP and NADPH from the light reaction.
  - CO₂ is fixed into organic molecules (like RuBP) and then reduced to form glucose.
  - RuBP is regenerated to continue the cycle.
Factors Affecting Photosynthesis Rate:
- External: Light intensity, CO₂ concentration, water availability, temperature, soil nutrients (affect chlorophyll).
- Internal: Chlorophyll content, leaf anatomy (size, shape, stomata density), stomatal conductance.

3. Mineral Nutrition

In addition to C, H, and O obtained from air and water, plants require essential mineral nutrients, mainly absorbed from the soil by roots.

Source: Primarily the soil.
Essential Mineral Elements: Plants require about sixteen nutrients.
- Macronutrients: Needed in large quantities (e.g., Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, Sulfur).
- Micronutrients: Needed in smaller quantities (e.g., Iron, Manganese, Zinc, Copper, Boron, Molybdenum, Chlorine).
Functions of Key Elements (Examples):
- Nitrogen (N): Proteins, nucleic acids, chlorophyll (leaf growth). Absorbed as NO₃⁻ or NH₄⁺.
- Phosphorus (P): Nucleic acids, ATP, cell membranes (root/flower/fruit development). Absorbed as phosphate ions.
- Potassium (K): Stomatal regulation, enzyme activation, water balance. Absorbed as K⁺.
- Calcium (Ca): Cell walls, cell signaling. Absorbed as Ca²⁺.
- Magnesium (Mg): Central atom in chlorophyll, enzyme activator. Absorbed as Mg²⁺.
- Sulfur (S): Amino acids (cysteine, methionine), vitamins, proteins. Absorbed as SO₄²⁻.
- Iron (Fe): Chlorophyll synthesis, electron transport. Absorbed as Fe³⁺.
- Manganese (Mn): Water splitting in photosynthesis, enzyme activation.
- Zinc (Zn): Enzyme activity, hormone synthesis.
Absorption of Minerals:
- Occurs via roots.
- Passive Absorption: Initial rapid uptake into cell wall space (apoplast), no energy required.
- Active Absorption: Slower uptake into cell interior (symplast), requires metabolic energy (ATP) as ions may be low concentration in soil or charged.
Studying Mineral Requirements:
- Hydroponics (Water Culture): Growing plants in nutrient solutions without soil to identify essential elements and deficiency symptoms by manipulating solution composition. Requires aeration.

4. Transportation in Plants

Plants have vascular tissues for internal transport:

Xylem:
- Transports water and dissolved minerals upwards from roots to leaves and other parts.
- Driving forces:
  - Root Pressure: Positive pressure from roots (especially at night).
  - Capillary Action: Water movement in narrow tubes due to adhesion/cohesion.
  - Transpiration Pull: Main force; negative pressure (tension) created by water evaporation from leaves (transpiration) pulling water up the xylem column.
Phloem:
- Transports sugars (food, mainly sucrose) from production sites (leaves - "source") to areas of use or storage ("sinks" - roots, fruits, growing points).
- Movement often explained by the "pressure-flow hypothesis".

5. Other Modes of Nutrition (Heterotrophic & Symbiotic)

While most are autotrophs, some plants utilize other nutritional strategies or relationships:

Heterotrophic Plants (Examples):
- Parasitic: Live on or inside a host plant, obtaining nutrients directly and often harming the host. (e.g., Cuscuta - dodder, which lacks chlorophyll; Mistletoe - partially parasitic, still photosynthesizes).
- Saprophytic: Obtain nutrition from dead and decaying organic matter by secreting digestive enzymes externally. (e.g., Indian Pipe plant; also common in fungi like mushrooms and mold, though fungi are not plants). Found in moist, dark environments.
- Insectivorous: Trap and digest insects to supplement mineral nutrition, particularly nitrogen, in nutrient-poor soils (e.g., swampy areas). They photosynthesize but get minerals from prey. (e.g., Pitcher plant, Venus flytrap, Bladderwort).
Symbiotic Relationships: Mutually beneficial associations with other organisms for enhanced nutrient uptake.
- Mycorrhizae: Fungi associate with plant roots, increasing the root surface area for water and mineral absorption (especially phosphorus) for the plant, while the fungus receives sugars from the plant.
- Nitrogen Fixation: Leguminous plants form root nodules housing Rhizobium bacteria. The bacteria convert atmospheric nitrogen gas (N₂) into a usable form (ammonia/ammonium) for the plant, in return receiving shelter and nutrients.

6. Nutrient Management in Agriculture

To replenish soil nutrients depleted by crops, farmers use:

Manure: Organic matter (decomposed plant/animal waste) improving soil structure and providing small amounts of nutrients.
Fertilizers: Commercially produced, concentrated sources of specific nutrients (e.g., NPK). Increase yield but can cause environmental issues if overused.
Biofertilisers: Living organisms (bacteria, fungi, cyanobacteria) that enrich soil nutrient quality, especially by fixing nitrogen or solubilizing phosphorus. (e.g., Rhizobium, Azospirillum, Azotobacter, blue-green algae).

Understanding these aspects of plant nutrition is vital for supporting plant life, agriculture, and maintaining ecological balance.

Ch-16 Plant Growth Regulators (PGRs)

Okay, here are the notes on Plant Growth Regulators (PGRs) organized logically and without duplication, drawing from all provided text sections.

Plant Growth Regulators (PGRs) / Phytohormones

I. Definition and Nature

Definition: Small, simple molecules of diverse chemical composition that control the rate of growth of plants.
Mechanism: Organic substances produced in small quantity in one part of the plant body and capable of moving to other parts to influence growth.
Origin: Can be naturally produced by plants or be synthetic chemicals resembling plant hormones in structure and function.
Efficacy: Effective even in very small quantities.

II. General Classification Based on their primary effects on plant growth:

Plant Growth Promoters: Involved in activities like cell division, cell enlargement, pattern formation, tropic growth, flowering, fruiting, and seed formation. (Includes Auxins, Gibberellins, Cytokinins).
Plant Growth Inhibitors: Play a role in responses to wounds and stresses, and inhibit growth activities like dormancy and abscission. (Includes Abscisic Acid).
Ethylene: Can fit into either group but is largely an inhibitor of growth activities (e.g., fruit ripening, senescence, abscission).

III. The Five Main Natural PGR Groups and Chemical Nature The five main groups of natural PGRs are:

Auxins: Indole compounds (e.g., indole-3-acetic acid (IAA), Indole-3-Butyric Acid (IBA)).
Gibberellins (GAs): Terpenes (e.g., Gibberellic Acid (GA₃), GA₁, GA₂ - over 100 identified).
Cytokinins: Adenine derivatives (e.g., Zeatin (natural), Kinetin (synthetic), Benzyladenine (synthetic)).
Abscisic acid (ABA): A derivative of carotenoids.
Ethylene: A gas (C₂H₄).

IV. Discovery of PGRs

The discovery of each major group was accidental:
- Auxin: First isolated from human urine; Fritz Went's experiment with oat seedlings demonstrated its existence.
- Gibberellins: Discovered through studying the 'bakane' disease of rice caused by the fungus Gibberella fujikuroi.
- Cytokinins: Discovered when F. Skoog found a substance in autoclaved herring sperm DNA (kinetin) was needed for tobacco callus proliferation alongside auxins.
- Ethylene: Discovered when Cousins confirmed a volatile substance from ripened oranges hastened ripening of unripened bananas.
- Abscisic acid (ABA): Initially discovered for its role in regulating abscission and dormancy.

V. Physiological Effects, Functions, and Uses of Specific PGRs

Auxins:
- Promote cell elongation.
- Promote cell division and differentiation (e.g., xylem differentiation).
- Help in initiating rooting in stem cuttings (widely used in propagation).
- Promote flowering (e.g., in pineapples).
- Help prevent fruit and leaf drop at early stages but promote the abscission of older, mature leaves and fruits.
- Induce apical dominance (inhibition of lateral buds by the apical bud). Decapitation overcomes this.
- Induce parthenocarpy (fruit development without fertilization) (e.g., in tomatoes).
- Used as herbicides (e.g., 2,4-D kills dicot weeds without affecting monocots).
- Examples: IAA, IBA (natural); NAA, 2,4-D (synthetic).
Gibberellins:
- Cause an increase in the length of the plant axis (stem elongation). Used to increase grape stalk length, sugarcane yield, and height of dwarf plants.
- Improve the shape of fruits (e.g., apple).
- Delay senescence, allowing fruits to be left on the tree longer.
- Used to speed up the malting process in the brewing industry.
- Hasten the maturity period in juvenile conifers, leading to early seed production.
- Promote bolting (internode elongation before flowering) in rosette plants (beet, cabbages).
- Break dormancy of seeds and buds.
- Examples: GA₃ (Gibberellic Acid) is the most studied, but many GAs exist.
Cytokinins:
- Strongly promote cell division (cytokinesis), which is their specific effect.
- Promote cell enlargement and cell differentiation.
- Help produce new leaves, chloroplasts, lateral shoots, and adventitious shoots.
- Overcome apical dominance and promote the growth of lateral buds/branching.
- Promote nutrient mobilization, which delays leaf senescence (aging).
- Synthesized in regions of rapid cell division (e.g., root apices, developing shoot buds, young fruits).
- Uses: Widely used in plant tissue culture to promote cell division and callus differentiation into shoots.
- Examples: Kinetin (synthetic), Zeatin (natural), Benzyladenine (synthetic).
Ethylene:
- The only known gaseous plant hormone.
- Promotes senescence and abscission of plant organs (leaves, flowers, fruits).
- Highly effective in fruit ripening and enhances the respiration rate during ripening (respiratory climactic).
- Breaks seed and bud dormancy; initiates germination (peanut) and sprouting (potato tubers).
- Promotes rapid internode/petiole elongation in deepwater rice to keep parts above water.
- Promotes root growth and root hair formation, increasing the absorption surface.
- Used to initiate flowering and synchronize fruit-set in pineapples and induces flowering in mango.
- Uses: Hasten fruit ripening (tomatoes, apples), accelerate abscission, promote female flowers (cucumbers).
- Most widely used compound: Ethephon (releases ethylene).
Abscisic Acid (ABA):
- Acts as a general plant growth inhibitor and an inhibitor of plant metabolism.
- Inhibits seed germination.
- Stimulates the closure of stomata in the epidermis, increasing stress tolerance (known as the "stress hormone").
- Plays an important role in seed development, maturation, and dormancy, helping seeds withstand desiccation and unfavorable conditions.
- In most situations, ABA acts as an antagonist to Gibberellins.
- Promotes the senescence of leaves.
- Uses: Can induce dormancy or stress tolerance in plants/seeds.
- Example: Abscisic Acid (ABA).

VI. Interactions and Influences

For every phase of growth, differentiation, and development, one or more PGRs play a role.
PGRs act in complex interactions (complementary, antagonistic, individualistic, or synergistic).
Interactions affect events like dormancy (seeds/buds), abscission, senescence, and apical dominance.
Extrinsic factors like temperature and light control plant growth/development via PGRs.
- Photoperiod duration can induce flowering (hypothesis of a hormonal substance like florigen).
- Vernalisation (low temperature exposure) affects flowering.

VII. Broader Role

PGRs are crucial intrinsic control factors alongside genomic control and extrinsic factors.
Influence various plant movements.

VIII. Conclusion

PGRs orchestrate the entire life cycle of a plant, from germination to senescence.
They adapt the plant's development to its environment through their complex interactions.

Ch-17 Sexual and Asexual Reproduction in Plants

Reproduction is the biological process by which organisms produce new individual organisms similar to themselves. It is fundamental for the continuation of species and the maintenance of life on Earth across generations.

Reproduction is broadly classified into two main types: Asexual Reproduction and Sexual Reproduction.

I. Asexual Reproduction

Definition: A mode of reproduction that involves only one parent and does not involve the fusion of gametes. Offspring produced are genetically identical to the parent, often referred to as "clones."

Types of Asexual Reproduction:

Binary Fission: The parent cell divides into two identical daughter cells. Common in unicellular organisms.
- Examples: Amoeba, Paramecium, Euglena.
Multiple Fission: The parent cell divides simultaneously into many daughter cells, often under adverse conditions.
- Examples: Plasmodium, Bacteria.
Budding: A small outgrowth or bud forms on the parent body, develops into a new organism, and then separates to live independently.
- Examples: Yeast, Hydra.
Fragmentation: The parent organism breaks into segments, and each segment develops into a complete new organism. Seen in simple multicellular organisms.
- Examples: Spirogyra, Starfish.
Sporulation: Organisms produce spores, which are reproductive structures that can develop into new individuals under favorable conditions. Spores are often lightweight for dispersal.
- Examples: Rhizopus (bread mold), ferns, algae.
Vegetative Propagation: A form of asexual reproduction in plants where new plants grow from vegetative parts (roots, stems, leaves) of the parent plant.
- Examples:
  - Stem: Potato, ginger, sugarcane
  - Leaves: Bryophyllum
  - Roots: Sweet potato
  - Artificial methods (Cuttings, Grafting): Rose, mango

Advantages of Asexual Reproduction:

Rapid population growth.
Only one parent is required.
Requires less energy and time.
High survival rate in stable environments.

Disadvantages of Asexual Reproduction:

Lack of genetic variation among offspring.
Low adaptability to environmental changes.
Slow pace of evolution due to no new trait development.

II. Sexual Reproduction

Definition: A mode of reproduction that typically involves two parents (male and female) and the fusion of their specialized reproductive cells (gametes) to form a zygote. This process introduces genetic variation, which is significant for evolution.

Stages of Sexual Reproduction:

Sexual reproduction is completed in three main stages:

Pre-fertilization Stage: Events occurring before the fusion of gametes.
- (i) Gametogenesis: Formation of male and female gametes (e.g., sperm and ovum). Male gametes are typically smaller and motile, while female gametes are larger and non-motile.
- (ii) Gamete Transfer: The process by which the male gamete reaches the female gamete for fertilization (e.g., pollination in plants, copulation in animals).
Fertilization Stage: The fusion of the male gamete with the female gamete to form a diploid cell called a zygote.
- Types of Fertilization:
  - Internal Fertilization: Fusion occurs inside the body of the female parent.
    - Examples: Humans, birds, mammals.
  - External Fertilization: Fusion occurs outside the body, usually in a water medium.
    - Examples: Frogs, fish.
Post-fertilization Events: Events that occur after the formation of the zygote, leading to the development of a new organism.
- The zygote undergoes cell division and differentiation to form an embryo.
- The embryo develops into a new organism.
- Types of Development:
  - Oviparous: Animals that lay eggs, and embryonic development occurs outside the mother's body.
    - Examples: Birds, reptiles.
  - Viviparous: Animals that give birth to live young ones, with embryonic development occurring inside the mother's body.
    - Examples: Mammals (humans, dogs).

Advantages of Sexual Reproduction:

Increases genetic variation, leading to greater adaptability.
Allows for the development of new and advantageous traits.
Favors natural selection by promoting the survival of individuals with more suitable traits.

Disadvantages of Sexual Reproduction:

Generally a more complex and time-consuming process.
The rate of offspring production is often lower compared to asexual reproduction.
Requires the involvement of two parents (in most cases).

Introduction: Reproduction is the fundamental biological process by which living organisms produce new individuals of their own kind, ensuring the continuation of the species. In plants, this occurs through two main methods: Asexual Reproduction and Sexual Reproduction.

1. Asexual Reproduction

Definition: Reproduction involving a single parent plant without the fusion of gametes.
Characteristics:
- Offspring are genetically identical clones of the parent.
- Allows for rapid multiplication of plants.
Methods of Asexual Reproduction in Plants:
- (i) Vegetative Propagation: New plants are produced from vegetative parts (roots, stems, leaves, buds).
  - Natural Methods: New plants arise naturally from specialized vegetative structures.
    - From Roots: Sweet potato, Carrot, Dahlia (adventitious roots).
    - From Stems:
      - Underground: Potato (tuber - 'eyes' are buds), Ginger (rhizome), Onion (bulb), Mint, Chrysanthemum (suckers).
      - Above Ground: Lawn grass (runners).
    - From Leaves: Bryophyllum (Kalanchoe) (adventitious buds on leaf margins).
    - Bulbils: Fleshy buds that detach (e.g., Oxalis, Pineapple).
  - Artificial Methods: Techniques used by humans for propagation.
    - Cutting: Planting a piece of stem or leaf (e.g., Rose, Sugarcane, Money plant).
    - Layering: Rooting a branch while it is still attached to the parent plant (e.g., Jasmine, Grapevine).
    - Grafting: Joining a part of one plant (scion) onto the root system of another (stock) (useful for seedless varieties, combining traits).
  - Advantages:
    - Plants mature and bear flowers/fruits earlier than those grown from seeds.
    - Enables propagation of plants that don't produce viable seeds (e.g., Banana, seedless Orange, Rose).
    - Offspring are genetically uniform, preserving desired traits.
    - Often quicker, easier, and less expensive than growing from seed.
  - Disadvantages:
    - Can lead to overcrowding if not managed.
    - Lack of genetic variation (except mutations).
    - Susceptibility to diseases can be uniform across the population.
- (ii) Spore Formation: Reproduction via specialized single-celled spores which develop into new individuals under favorable conditions.
  - Examples: Ferns, Mosses (Bryophytes & Pteridophytes), Fungi (e.g., Rhizopus - in sporangia), Algae (e.g., zoospores). Spores are often protected by thick walls.
- (iii) Fragmentation: The parent body breaks into fragments, each growing into a new individual.
  - Example: Spirogyra (a filamentous alga).
- (iv) Budding: A small outgrowth (bud) forms on the parent, detaches, and grows into a new independent individual.
  - Example: Yeast (a single-celled fungus). Also occurs in multicellular organisms like Hydra.
- (v) Micropropagation (Tissue Culture): Growing plants from a small piece of tissue or cells in a sterile nutrient medium.
  - Tissue forms a callus, which develops into plantlets.
  - Allows rapid production of large numbers of identical plants from a small amount of parent material.
  - Based on cell totipotency. Used for Orchids, Carnations, Asparagus.
- (vi) Apomixis: Seed formation without fertilization and meiosis; a type of asexual reproduction mimicking sexual reproduction.
  - Examples: Dandelions, some grasses, Citrus, Mango.
  - Embryo can develop from an unfertilized diploid egg or somatic cells of the ovule.

2. Sexual Reproduction

Definition: Reproduction involving the fusion of male and female gametes to form a zygote, which develops into a new plant.
Characteristics:
- Usually involves two parents (or distinct male/female parts).
- Results in genetic variation in offspring, combining traits from both parents, contributing to adaptation and evolution.
- Occurs primarily in the flower in flowering plants (Angiosperms).

2.1 Flower Structure (in Flowering Plants)

The flower is the reproductive organ, typically composed of four whorls:

1. Calyx (Sepals): Outermost whorl, usually green, protects the flower bud.
2. Corolla (Petals): Often brightly colored/scented, attracts pollinators.
3. Androecium (Stamens): Male reproductive parts.
- Stamen: Consists of a Filament (stalk) and an Anther (contains pollen sacs).
- Anther: Produces Pollen Grains, which contain the male gametes.
4. Gynoecium/Pistil (Carpels): Female reproductive part, typically in the center.
- Pistil: Consists of Stigma (receptive tip for pollen), Style (stalk), and Ovary (swollen base containing ovules).
- Ovary: Contains Ovules, which contain the female gamete (egg cell).
- Flowers can be Unisexual (having only stamens or pistils, e.g., Papaya, Watermelon) or Bisexual (having both, e.g., Hibiscus, Mustard).

2.2 Gametogenesis (Formation of Gametes in Flowering Plants)

Microsporogenesis: Formation of microspores (pollen grains) from microspore mother cells in the anther via meiosis. Pollen grain develops into the male gametophyte containing a vegetative cell and a generative cell (or two male gametes).
Megasporogenesis: Formation of megaspores within the ovule via meiosis. One functional megaspore develops into the female gametophyte (embryo sac) through mitosis. A typical embryo sac is 7-celled, 8-nucleate, containing the egg cell, synergids, antipodal cells, and a central cell with polar nuclei.

2.3 Process of Sexual Reproduction in Flowering Plants

(i) Pollination: Transfer of pollen grains from the anther to the stigma.
- Self-Pollination: Pollen transfer to the stigma of the same flower or another flower on the same plant. (Cleistogamous flowers self-pollinate without opening).
- Cross-Pollination: Pollen transfer to the stigma of a flower on a different plant of the same species. (Adaptations like dichogamy, self-incompatibility prevent self-pollination).
- Pollinating Agents: Abiotic (Wind - anemophily, Water - hydrophily) or Biotic (Insects - entomophily, Birds - ornithophily, Animals).
(ii) Fertilization: The pollen grain germinates on the stigma, growing a pollen tube down the style to reach the ovule. Male gametes travel down the pollen tube.
- Double Fertilization: Unique to angiosperms.
  - One male gamete fuses with the egg cell (Syngamy) forming the diploid Zygote (develops into the embryo).
  - The other male gamete fuses with the diploid secondary nucleus in the central cell (Triple Fusion) forming the triploid Primary Endosperm Nucleus (PEN) (develops into the endosperm, nutritive tissue).
- Synergids and antipodal cells typically degenerate after fertilization.
(iii) Post-fertilization Events (Seed and Fruit Formation):
- The Ovule develops into a Seed. The seed contains the embryo (from zygote), stored food (endosperm/cotyledons), and a protective seed coat (from ovule integuments). Seeds often undergo dormancy and are dispersed (wind, water, animals). Seed germination leads to a new seedling.
- The Ovary matures and develops into a Fruit. The fruit protects the seeds and aids in dispersal.
- Other flower parts (petals, sepals, stamens, style, stigma) usually wither.
- Parthenocarpic fruits develop without fertilization (e.g., Banana) and are usually seedless. Polyembryony (multiple embryos in a seed) can occur.

3. Reproduction in Lower Plants

Lower plants (Algae, Bryophytes, Pteridophytes) often exhibit Alternation of Generations (alternating haploid gametophyte and diploid sporophyte phases).

Algae: Reproduce by fragmentation, spores (e.g., zoospores), and sexual fusion of gametes (isogamy, anisogamy, oogamy).
Bryophytes (Mosses, Liverworts): Dominant body is haploid gametophyte. Gametes produced in antheridia (male) and archegonia (female). Fertilization requires water, forming a zygote which develops into a dependent sporophyte. Sporophyte produces haploid spores by meiosis. Vegetative reproduction by fragmentation/budding.
Pteridophytes (Ferns, Horsetails): Dominant body is diploid sporophyte with vascular tissue. Sporangia produce haploid spores by meiosis. Spores germinate into a small, independent gametophyte (prothallus). Gametes produced on the gametophyte. Fertilization requires water, forming a zygote that grows into a new sporophyte.

4. Relationship with Growth and Development

Reproduction is integrated with plant growth and development. Plants undergo vegetative growth before entering the reproductive phase, often triggered by environmental signals (photoperiod, temperature) and regulated by plant hormones (auxins, gibberellins, etc.) which influence processes like flowering, fruit set, and seed germination.

Summary: Asexual reproduction involves a single parent producing identical offspring rapidly. Sexual reproduction involves gamete fusion, producing genetically varied offspring, crucial for adaptation and evolution. Both methods are vital for plant propagation and species survival.

Ch-18 Important medicinal plants with special reference to Rajasthan

Introduction: Plants have been a cornerstone of traditional medicine for millennia and continue to be a vital source of drugs and therapeutic compounds in modern healthcare. Their importance spans historical healing practices, ongoing drug discovery, and ecological roles.

1. Historical and Traditional Significance

Ancient Practices: In ancient societies, intellectuals recognized and utilized various plants for curing diseases and promoting health and longevity. This practice was historically known as Rasayana in some traditions.
Early Alchemy and Medicine: The term 'Rasayana' itself was sometimes used as a synonym for chemistry in Sanskrit and other Indian languages, highlighting the deep connection between early chemical understanding and medicinal preparations.
Integration with Other Substances: Indian alchemists like Nagarjuna initiated the practice of combining metals with medicinal plants in their formulations, documented in texts like the Rasa sastra classics (8th-16th centuries). Modern chemical research can still find valuable insights by exploring the ancient principles mentioned in these historical texts.
Traditional Remedies: Historical medicinal systems, including Indian and Chinese traditions, developed specific plant-based remedies and practices (e.g., the historical use of skin crusts from smallpox victims, which, while not purely plant-based, falls under traditional immunological practices often linked with natural remedies).

2. Plants as a Source of Modern Drugs

Major Source of Pharmaceuticals: Plants remain an incredibly important source for pharmaceuticals today. More than 25% of the drugs currently sold worldwide are derived from plants.
Traditional Knowledge Base: An estimated 25,000 plant species are utilized in traditional medicines by native peoples globally, providing a vast pool of potential candidates for modern drug discovery.
Bioprospecting: There is ongoing scientific exploration, termed 'bioprospecting,' to investigate the molecular, genetic, and species-level diversity of plants to identify economically important products, with a significant focus on finding new medicines.

3. The Chemical Basis: Secondary Metabolites

Production of Compounds: Plants produce a wide variety of organic compounds beyond those directly needed for basic growth and metabolism (primary metabolites). These are called secondary metabolites, including colored pigments, scents, gums, and spices.
Role in Welfare: While the precise ecological roles of all secondary metabolites are still being studied, many have been found to be highly useful for human welfare, particularly as drugs.
Active Principles: Complex organic compounds like alkaloids, found in many medicinal plants, are often the active principles responsible for their therapeutic effects.
- Examples: Quinine from the Cinchona plant and morphine from Papaver species are well-known examples of important drugs derived from plant alkaloids.

4. Specific Examples of Medicinal Plants and Their Applications

Willow Tree: The bark was traditionally used for pain relief. It was later found to contain compounds related to 2-hydroxy benzoic acid, which led to the development of aspirin.
Rauwolfia serpentina (Sarpagandha): Used in Ayurvedic medicine for treating hypertension. The active component, reserpine, was isolated and became one of the first effective modern medicines for controlling high blood pressure.
Cinchona officinalis: The source of quinine, one of the earliest and most important drugs used for the treatment of malaria. Initially extracted from the bark, quinine was later synthesized.
Other Plants Mentioned:
- Plants in the Solanaceae family known for medicinal importance include Belladonna and Ashwagandha.
- Plants in the Liliaceae family mentioned for medicinal use include Aloe barbadensis (Ghrit kumari) and Asparagus racemosus (Shatawar or Satmuli).
- Common kitchen plants/spices with traditional medicinal properties include Turmeric, Basil, Garlic, Ginger, Black pepper, and Cloves (often knowledge passed down by elders).

5. Specific Traditional Remedies and Uses

Nettle Stings: Rubbing the affected area with the leaf of the dock plant is a traditional remedy used to soothe nettle stings (caused by methanoic acid).
Grain Storage: Dried neem leaves are traditionally used for storing food grains at home to protect them from pests.

6. Modern Context and Future Outlook

Government Initiatives: Initiatives like India's 'National Gardening Mission' aim to enhance horticulture and gardening, which can potentially include the cultivation and propagation of medicinal plants using methods like organic farming.
Value of Knowledge: The significance of traditional knowledge regarding medicinal plants is increasingly recognized as a valuable resource for modern scientific investigation and drug discovery.

Conclusion: Medicinal plants represent a rich heritage of human knowledge and a crucial resource for current and future healthcare. Their importance is rooted in ancient traditions, validated by modern scientific discoveries, and continues to drive the search for new therapeutic agents from the diverse plant kingdom. Utilizing and preserving this plant diversity is essential for both ecological balance and human well-being.

Ch-19 Organic Farming

Introduction: Organic farming is an agricultural system that prioritizes ecological balance, biodiversity conservation, and sustainable resource management. It aims to produce high-quality crops while minimizing environmental harm and protecting human health, primarily by avoiding synthetic chemicals.

1. Core Principles and Philosophy

Working with Nature: Organic farming operates in harmony with natural ecological processes rather than seeking to dominate or override them.
Environmental Protection: It aims to avoid adverse effects on the natural environment, including soil, water, and air quality.
Human Health: It seeks to protect human health by minimizing exposure to chemical residues in food and the environment.
High-Quality Yields: While different in approach, a goal remains the production of nutritious and high-quality crops.
Cyclical, Zero-Waste System: Organic farming encourages a holistic approach where waste from one process (like livestock excreta or crop residue) becomes a valuable input (like manure) for another, maximizing resource utilization and efficiency.

2. Key Techniques and Components

Organic farming relies heavily on natural inputs and ecological processes:

Input Minimization/Elimination:
- Minimal or no use of chemical fertilizers, synthetic herbicides, and synthetic pesticides.
Maximizing Organic Inputs:
- Organic Manures: Central to soil fertility. These are derived from biological waste.
  - Examples include compost, vermicompost (using earthworms to create nutrient-rich, balanced manure), and farmyard manure (FYM).
- Recycled Farm Wastes: Utilizing crop residues (straw) and livestock excreta.
Utilizing Bio-Agents:
- Biofertilisers: Organisms that naturally enrich the nutrient quality of the soil.
  - Main sources include bacteria, fungi, and cyanobacteria (blue-green algae).
  - Examples: Rhizobium bacteria in the root nodules of legumes fix atmospheric nitrogen; free-living bacteria like Azospirillum and Azotobacter also enrich soil nitrogen. Cultures of blue-green algae are used in biofertiliser preparation.
- Bio-pesticides: Natural substances or organisms used to control pests and diseases.
  - Examples: Neem leaves or turmeric used traditionally in grain storage. Bacillus thuringiensis (Bt) toxin, derived from a bacterium, can be used as a natural insecticide spray or even expressed in genetically modified (GM) plants (though the use of GM plants might be debated within strict organic certification standards, the Bt toxin itself is a bio-pesticide concept relevant to reducing chemical use).
Implementing Healthy Cropping Systems:
- Mixed Cropping: Growing two or more crops simultaneously in the same field.
- Inter-cropping: Growing two or more crops simultaneously in alternate rows or patterns.
- Crop Rotation: Growing different types of crops sequentially on the same land across seasons or years.
- Benefits of Cropping Systems: These practices help in nutrient utilization, breaking pest and disease cycles, controlling weeds, and maintaining soil fertility and structure.
Biological Control of Pests and Diseases:
- Managing pests and diseases by using their natural enemies (predators, parasites, pathogens) rather than introducing synthetic chemicals. The aim is to keep pest populations at manageable levels, not necessarily eradication, within a balanced ecosystem.

3. Benefits of Organic Farming

Environmental Advantages:
- Protects the environment from pollution caused by excessive chemical fertilizers and pesticides.
- Enhances soil health and fertility naturally (prevents soil degradation from chemical overuse).
- Supports biodiversity (beneficial insects, microbes).
- Contributes to a zero-waste system through recycling farm waste.
Soil Health Improvement:
- Organic manure significantly enhances the soil's water-holding capacity.
- Makes the soil more porous, improving aeration and gas exchange.
- Increases the population of beneficial soil microbes.
- Improves soil texture and structure.
Reduced Chemical Dependency: Less reliance on expensive and potentially harmful synthetic inputs.
Sustainability: Encouraged as a method to sustain the benefits achieved by the Green Revolution in a more environmentally sound way, using limited chemicals in conjunction with biofertilisers where needed, to avoid harm to farms and human health.

4. Comparison with Conventional Farming

Conventional Farming: Often relies heavily on synthetic chemicals (fertilizers, pesticides, herbicides) to maximize yields. This can lead to indiscriminate killing of both harmful and beneficial organisms, soil degradation (acidity, reduced fertility over time), water pollution, and harm to soil microorganisms.
Organic Farming: Takes a more holistic, ecosystem-based approach, prioritizing soil health, biological processes, and natural inputs over synthetic chemicals. Organic manure, while perhaps less concentrated in specific nutrients than synthetic fertilizers, is considered superior for overall long-term soil health due to its multiple positive effects on soil structure, biology, and water retention.

5. Examples and Case Studies

Integrated Organic Farming: The example of Ramesh Chandra Dagar in Haryana, India, demonstrates a self-sustaining, integrated approach combining elements like bee-keeping, dairy, water harvesting, composting, and agriculture within an organic framework.
Ecological Waste Management: The case study of wastewater treatment in Arcata, California, illustrates ecological principles (using plants, algae, fungi, bacteria) for purification, reflecting the broader organic philosophy of working with natural systems.

6. Government Encouragement

Governments, including the Indian government, are increasingly encouraging sustainable organic farming practices through awareness campaigns and policy initiatives.
The establishment of programs like India's 'National Gardening Mission' aims to promote horticulture, potentially incorporating organic methods.

Conclusion: Organic farming represents a vital shift towards more sustainable and environmentally responsible agriculture. By focusing on soil health, biodiversity, and the use of natural inputs and processes, it offers a pathway to producing food that is better for the environment and human health, while also building more resilient farming systems.

Ch-20 Biotechnology and its applications

I. Definition of Biotechnology

General Definition: Using live organisms or enzymes from organisms to produce products and processes useful to humans.
Restricted/Modern Definition: Often refers to processes using genetically modified organisms (GMOs) on a larger scale.
European Federation of Biotechnology (EFB) Definition: Integration of natural science and organisms, cells, parts thereof, and molecular analogues for products and services.

II. Core Techniques Enabling Modern Biotechnology

Genetic Engineering:
- Techniques to alter the chemistry of genetic material (DNA and RNA).
- Introduce altered material into host organisms to change their phenotype.
- Also called recombinant DNA (rDNA) technology.
Maintenance of Sterile Ambience:
- Ensuring microbial contamination-free environment in chemical engineering processes.
- Enables growth of only the desired microbe/eukaryotic cell in large quantities.
- Used for manufacturing products like antibiotics, vaccines, enzymes, etc..

III. Principles and Processes of Biotechnology

Recombinant DNA Technology (Genetic Engineering): ("Cut and Paste" technology)
- Steps:
  - Isolation: Obtain the desired gene (DNA segment) with a specific nucleotide sequence.
  - Cutting: Cut DNA at specific sites using restriction enzymes ('molecular scissors'), which often leave 'sticky ends'.
  - Vector Choice: Select a vector (e.g., plasmid in bacteria, viruses like bacteriophages) to carry the foreign DNA into the host. Plasmids can replicate autonomously.
  - Ligation: Insert the desired gene into the vector DNA using DNA ligase to join the cut DNA molecules, creating recombinant DNA.
  - Introduction into Host: Introduce recombinant DNA into a host organism (e.g., Escherichia coli). Methods include:
    - Incubation on ice + heat shock.
    - Micro-injection (animal cells).
    - Biolistics or gene gun (plant cells).
    - Using disarmed pathogen vectors.
  - Cloning: The host cell replicates, making multiple copies of the recombinant DNA, thereby cloning the foreign gene.
  - Expression: The foreign gene is expressed to produce the desired protein.
  - Purification & Formulation: Isolate and purify the gene product (functional protein) and formulate for marketing.
  - Large-scale Production: Carried out in bioreactors (often stirring type).
Polymerase Chain Reaction (PCR):
- Used to amplify a segment of DNA to approximately billion times.
- Involves repeated replication using primers and a thermostable DNA polymerase.

IV. Applications of Biotechnology

Agriculture:
- Genetically Modified (GM) Crops / Transgenic Plants:
  - Pest-resistant plants: Incorporating the Bt toxin gene from Bacillus thuringiensis into crops (e.g., Bt cotton, Bt corn, rice, tomato, potato, soybean). Acts as a bio-pesticide. Specific cry genes (cryIAc, cryIIAb for cotton bollworms; cryIAb for corn borer).
  - Herbicide-resistant plants.
  - Improved nutritional value (Biofortification): Breeding crops with higher vitamins, minerals, protein, healthier fats (e.g., maize with lysine/tryptophan, wheat variety Atlas 66 with high protein, iron-fortified rice).
  - Plants supplying alternative resources (starches, fuels, pharmaceuticals).
- Tissue Culture:
  - Regenerating whole plants from explants in vitro using special nutrient media (totipotency).
  - Leads to micro-propagation (thousands of identical plants/ somaclones in short duration - e.g., tomato, banana, apple).
  - Used for recovering healthy plants from diseased plants by growing virus-free meristems.
- Somatic Hybridization:
  - Fusion of protoplasts from two different plant varieties with desirable traits.
  - Creates somatic hybrids (e.g., tomato-potato, "Ptomato", though not commercially successful).
Medicine:
- Recombinant Therapeutics: Mass production of safe and more effective therapeutic drugs (e.g., human insulin, growth hormone, erythropoietin, interferons, clotting factors, monoclonal antibodies). ~30 approved worldwide, 12 in India.
- Diagnostics: Development of new tools for disease diagnosis.
- Transgenic Animals:
  - Study of disease: Models for human diseases (cancer, cystic fibrosis, rheumatoid arthritis, Alzheimer’s) to study treatments.
  - Biological products: Producing useful, often expensive, biological products (e.g., transgenic cow Rosie produced human protein-enriched milk with alpha-lactalbumin; attempts for PKU, cystic fibrosis).
- Gene Therapy:
  - Replacing defective genes with healthy ones to treat genetic disorders (e.g., SCID).
  - Adding functional normal genes to correct inherited defects.
  - Approaches: Somatic gene therapy (ex-vivo, in-vivo, antisense therapy); Germ-line gene therapy (not currently practiced).
- Vaccines:
  - Development of bioengineered vaccines (e.g., rabies, hepatitis B) by inserting antigen genes into plasmids.
Industry:
- Biopharmaceuticals and biologicals: Produced using GM microbes, fungi, plants, and animals (overlaps with Medicine).
- Industrial Enzymes: Produced using cloned genes (e.g., proteases, amylases, glucoisomerases for detergents, food, textiles).
- Food Processing: Using microorganisms in fermentation for cheese, yoghurt, alcohol (e.g., Streptococcus thermophilus, Lactobacillus bulgarians for yoghurt; yeast for alcohol).
- Bioremediation: Using organisms/enzymes to clean up toxic and hazardous substances (overlaps with Environment).
Environment:
- Bioremediation: Cleaning up pollutants using naturally occurring or GM microorganisms/enzymes.
- Biopesticides: Reducing reliance on chemical pesticides (e.g., Bt toxin).
Forensics:
- DNA fingerprinting: Identification of criminals using genetic knowledge.

V. Ethical Issues

Concerns regarding manipulation of organisms.
Biosafety
Biopiracy (exploiting biological resources without authorization)
Biopatents

VI. Conclusion

Biotechnology is a rapidly evolving field with immense potential across health, agriculture, environment, and industry.

Biology ​

Ch-1 The Cell ​

Ch-2 Control and Coordination ​

Ch-3 Reproduction in Human Beings ​

Human Reproductive System: ​

Process of Human Reproduction ​

Reproductive Hormones in Humans ​

Ch-4: Excretion in Human beings ​

Ch-5 Respiration in Human Beings ​

Ch-6 Circulation System in Human beings ​

Ch-7 Digestive System in Human Being ​

Ch-8 Blood Groups, Blood Composition, and Function ​

Ch-9 Hormones ​

Ch-10 Genetic and Lifestyle Diseases ​

Ch-11 Human Diseases: Communicable & Non-Communicable Diseases ​

Communicable Diseases ​

1. Bacterial Diseases ​

(a) Airborne Bacterial Diseases ​

(b) Water & Foodborne Bacterial Diseases ​

(c) Sexually & Skin Transmitted Bacterial Diseases ​

(d) Vector-Borne Bacterial Diseases ​

Prevention of Bacterial Diseases ​

2. Viral Diseases ​

(a) Airborne Viral Diseases ​

(b) Water and Foodborne Viral Diseases ​

(c) Vector-Borne Viral Diseases ​

(d) Sexually and Blood Transmitted Viral Diseases ​

Prevention of Viral Diseases ​

3. Fungal Diseases ​

(a) Skin and Nail Fungal Diseases ​

(b) Oral and Genital Fungal Infections ​

(c) Systemic Fungal Infections ​

Prevention of Fungal Diseases ​

4. Parasitic Diseases ​

(a) Vector-Borne Parasitic Diseases ​

(b) Water & Foodborne Parasitic Diseases ​

(c) Helminthic Parasitic Diseases (Worms) ​

Prevention of Parasitic Diseases ​

Non-Communicable Diseases (NCDs) ​

(a) Genetic Diseases ​

(i) Single Gene Disorders ​

(ii) Chromosomal Disorders ​

(iii) Metabolic Disorders ​

Prevention/Management of Genetic Diseases ​

(b) Hormonal Disorders ​

(i) Thyroid Gland Related Disorders ​

(ii) Pancreas Related Disorders ​

(iii) Adrenal Gland Related Disorders ​

(iv) Pituitary Gland Related Disorders ​

(v) Reproductive Hormone Disorders ​

(vi) Other Hormonal Disorders ​

Prevention of Hormonal Disorders ​

(c) Cardiovascular Diseases (CVDs) ​

Heart Disease Prevention ​

Heart Disease Diagnostic Tests ​

Heart Disease Treatments ​

(d) Cancer ​

Causes of Cancer ​

Symptoms of Cancer ​

Diagnosis of Cancer ​

Treatment of Cancer ​

Prevention of Cancer ​

(e) Neurological Disorders ​

(i) Neurodegenerative Diseases ​

(ii) Autoimmune Neurological Disorders ​

(iii) Infectious Neurological Diseases ​

(iv) Peripheral Neuropathy Disorders ​

(v) Other Neurological Disorders ​

Prevention of Neurological Disorders ​

(f) Mental Disorders ​

(i) Mood Disorders ​

(ii) Anxiety Disorders ​

(iii) Psychotic Disorders ​

(iv) Personality Disorders ​

(v) Trauma & Stress-related Disorders ​

(vi) Eating Disorders ​

(vii) Childhood & Developmental Disorders ​

Prevention and Management of Mental Disorders ​

(g) Bone Disorders ​

(i) Bone Density Disorders ​