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1. MOTION

Types of Motion:

  • Linear/Translational: Car moving on road
  • Rotational: Ceiling fan, Earth's rotation
  • Oscillatory: Pendulum clock, swing
  • Vibrational: Guitar string, tuning fork

Daily Examples:

  • Newton's First Law: Sudden bus stop → passengers fall forward
  • Second Law: Cricket — harder hit → faster ball
  • Third Law: Swimming (push water back, move forward)

2. HEAT

Modes of Heat Transfer:

  • Conduction: Metal spoon in hot tea
  • Convection: Boiling water, AC cooling
  • Radiation: Sunlight, microwave cooking

Important Concepts:

  • Specific Heat: Water > Sand → Sea breeze / land breeze
  • Thermal Expansion: Railway gaps, bridges with expansion joints
  • Latent Heat: Ice → water → steam

3. LIGHT

Properties:

  • Reflection: Mirrors, periscope
  • Refraction: Spoon bent in water, rainbow
  • Dispersion: Prism → VIBGYOR spectrum
  • Scattering: Blue sky (Rayleigh scattering), red sunrise/sunset

Lenses:

  • Convex: Converging (magnifying glass, human eye)
  • Concave: Diverging (spectacles for myopia)

Defects of Vision:

Defect Problem Correction
Myopia Distant blur Concave lens
Hypermetropia Near blur Convex lens
Presbyopia Age-related near blur Bifocal lenses
Astigmatism Distorted vision Cylindrical lens

4. PRESSURE

Applications:

  • Hydraulic Lift: Pascal's law — small force lifts heavy objects
  • Syringe: Medical injections
  • Air Pressure: Drinking straw, suction cups

Atmospheric Pressure:

  • Mercury Barometer: 76 cm Hg at sea level
  • Decreases with altitude → nose bleeding at hills
  • Increase → clear weather, Decrease → storm

5. FLOATATION

Archimedes’ Principle: Upthrust = Weight of displaced fluid

Applications:

  • Ships (hollow shape increases volume)
  • Submarines (ballast tanks)
  • Hydrometers (measure liquid density)
  • Hot air balloons (less dense than air)

6. CURRENT ELECTRICITY

  • Ohm's Law: V = IR
  • Series Circuit: Current same, voltage divides
  • Parallel Circuit: Voltage same, current divides

Household Safety:

  • Fuse: Overcurrent protection (melts)
  • MCB: Automatic switch-off
  • Earthing: Prevents shock (green wire)
  • Insulation: PVC coating on wires

7. MAGNETISM

Properties:

  • Like poles repel, unlike attract
  • Magnetic field lines: North to South
  • Curie Temperature: Iron loses magnetism at 770°C

Applications:

  • Compass navigation
  • MRI in medicine
  • Electric motors/generators
  • Credit card magnetic strips

8. SURFACE TENSION

Definition: Liquid surface behaves like stretched membrane

Examples:

  • Water droplets spherical
  • Insects walk on water (pond skaters)
  • Razor blade floats if placed carefully
  • Capillary action: Water rises in thin tube

Factors Reducing Surface Tension:

  • Adding soap/detergent
  • Increasing temperature
  • Adding impurities

9. VISCOSITY

Definition: Internal friction/resistance to flow

Examples:

  • Honey > Water > Air (viscosity order)
  • Stoke's Law: Determines terminal velocity
  • Poiseuille's Law: Flow through pipes

Temperature Dependence:

  • Liquids: Viscosity ↓ with temperature ↑
  • Gases: Viscosity ↑ with temperature ↑

10. WORK, ENERGY & POWER

Work (W) = F × s × cosθ

  • Positive work: Force & displacement same direction
  • Negative work: Opposite direction (braking)
  • Zero work: Force perpendicular to displacement

Energy Forms:

  • Kinetic Energy: KE = ½mv²
  • Potential Energy: PE = mgh
  • Law of Conservation: Energy neither created nor destroyed

Power = Work/Time (Watt)

  • 1 HP = 746 Watts

11. GRAVITATION

Newton's Law: F = G(m₁m₂)/r²

Acceleration due to gravity (g):

  • Value: 9.8 m/s²
  • Varies with: Altitude (↓), Depth (↓), Latitude (max at poles)

Satellite Motion:

  • Geostationary: 36,000 km, fixed position
  • Polar: 500–800 km, covers poles

12. ELASTICITY

  • Stress = Force / Area
  • Strain = Change in dimension / Original dimension
  • Young's Modulus = Stress / Strain

Hooke's Law: F = kx (within elastic limit)

Applications: Spring balance, shock absorbers

13. SIMPLE HARMONIC MOTION

Conditions: Acceleration ∝ − Displacement

Examples:

  • Simple pendulum: T = 2π√(l/g)
  • Mass on spring: T = 2π√(m/k)
  • Swing, vibrating string

14. WAVE MOTION

Types:

  • Transverse: Light, water waves (vibration perpendicular)
  • Longitudinal: Sound (vibration parallel)

Wave Equation: v = fλ

Doppler Effect: Frequency change due to relative motion

  • Approaching → Higher pitch
  • Receding → Lower pitch

15. SOUND WAVE

Characteristics:

  • Infrasonic: < 20 Hz (elephants communicate)
  • Audible: 20 Hz – 20 kHz
  • Ultrasonic: > 20 kHz (bats, medical imaging)

Sound Properties:

  • Needs medium (vacuum: no sound)
  • Speed: Solids > Liquids > Gases
  • Air: 332 m/s at 0°C, increases 0.6 m/s per °C rise

16. STATIC ELECTRICITY

Triboelectric Effect: Friction → Charge transfer

Examples:

  • Comb through hair attracts paper
  • Lightning (cloud–ground discharge)
  • Photocopier operation

Electrostatic Applications:

  • Spray painting
  • Air filters
  • Inkjet printers

17. SCIENTIFIC INSTRUMENTS

Instrument Measures Principle
Barometer Atmospheric pressure Mercury column height
Hygrometer Humidity Hair expansion / condensation
Anemometer Wind speed Rotating cups
Seismograph Earthquake waves Pendulum recording
Lactometer Milk purity Floatation principle
Hydrometer Liquid density Floatation depth
Spectrometer Light wavelength Prism dispersion
Manometer Gas pressure Liquid column difference

18. INVENTIONS

Invention Inventor Year Country
Telescope Galileo Galilei 1609 Italy
Steam Engine James Watt 1765 Scotland
Electric Bulb Thomas Edison 1879 USA
Radio Guglielmo Marconi 1895 Italy
Airplane Wright Brothers 1903 USA
Television John Logie Baird 1926 Scotland
Computer Charles Babbage 1837 UK
Telephone Alexander Graham Bell 1876 Scotland / USA
X-ray Wilhelm Roentgen 1895 Germany
Penicillin Alexander Fleming 1928 Scotland

19. ATOMIC & NUCLEAR PHYSICS

Atomic Structure:

  • Protons: +ve charge, nucleus
  • Neutrons: Neutral, nucleus
  • Electrons: −ve charge, orbits

Nuclear Reactions:

  • Fission: Heavy nucleus splits (Nuclear reactor)
  • Fusion: Light nuclei combine (Sun, Hydrogen bomb)

Radioactivity:

  • α-particles: He nucleus (least penetration)
  • β-particles: Electrons (medium penetration)
  • γ-rays: Electromagnetic waves (highest penetration)

Half-life: Time for half of atoms to decay

  • Carbon-14: 5730 years (carbon dating)

20. ELECTRONICS

Components:

  • Resistor: Limits current
  • Capacitor: Stores charge
  • Diode: Allows current one way
  • Transistor: Amplifies / switches current

Logic Gates:

  • AND, OR, NOT, NAND, NOR, XOR
  • Basis of digital circuits

21. VARIOUS UNITS OF MEASUREMENT

SI Base Units:

  • Length: meter (m)
  • Mass: kilogram (kg)
  • Time: second (s)
  • Current: ampere (A)
  • Temperature: kelvin (K)
  • Luminous intensity: candela (cd)
  • Amount of substance: mole (mol)

Weight / Mass Units:

  • 1 metric ton = 1000 kg
  • 1 quintal = 100 kg
  • 1 kg = 1000 g
  • 1 carat = 200 mg (gemstones)

Important Scientific Discoveries

Discovery Scientist Year
Law of Gravitation Isaac Newton 1687
Laws of Motion Isaac Newton 1687
Electromagnetic Induction Michael Faraday 1831
Radioactivity Henri Becquerel 1896
Photoelectric Effect Albert Einstein 1905
Theory of Relativity Albert Einstein 1905 / 1915
Uncertainty Principle Werner Heisenberg 1927
Neutron Discovery James Chadwick 1932
Nuclear Fission Otto Hahn, Fritz Strassmann 1938
Superconductivity Heike Kamerlingh Onnes 1911

Pressure Units:

  • 1 atm = 760 mm Hg = 101325 Pa
  • 1 bar = 10⁵ Pa
  • 1 psi = 6895 Pa

22. IMPORTANT DISCOVERIES IN PHYSICS

Discovery Scientist Year
Law of Gravitation Isaac Newton 1687
Laws of Motion Isaac Newton 1687
Electromagnetic Induction Michael Faraday 1831
Radioactivity Henri Becquerel 1896
Photoelectric Effect Albert Einstein 1905
Theory of Relativity Albert Einstein 1905 / 1915
Uncertainty Principle Werner Heisenberg 1927
Neutron Discovery James Chadwick 1932
Nuclear Fission Otto Hahn, Fritz Strassmann 1938
Superconductivity Heike Kamerlingh Onnes 1911

23. UNIT CONVERSIONS

Length:

  • 1 km = 1000 m = 0.621 miles
  • 1 m = 100 cm = 39.37 inches
  • 1 inch = 2.54 cm

Mass:

  • 1 kg = 2.2046 pounds
  • 1 pound = 453.6 g

Temperature:

  • °C to °F: F = (9/5)C + 32
  • °F to °C: C = (5/9)(F − 32)
  • K = C + 273.15

Energy:

  • 1 calorie = 4.184 joules
  • 1 kWh = 3.6 × 106 J
  • 1 eV = 1.6 × 10−19 J

1. SUBSTANCE & ITS NATURE

Classification:

  • Elements: 118 known (94 natural)
  • Compounds: Fixed composition (H₂O, NaCl)
  • Mixtures: Variable composition

States of Matter:

  • Solid: Fixed shape/volume (ice)
  • Liquid: Fixed volume, takes container shape (water)
  • Gas: No fixed shape/volume (steam)
  • Plasma: Ionized gas (stars, lightning)

2. OXIDATION & REDUCTION

Definitions:

  • Oxidation: Loss of electrons, gain of oxygen
  • Reduction: Gain of electrons, loss of oxygen
  • Oxidizing Agent: Gets reduced (accepts electrons)
  • Reducing Agent: Gets oxidized (donates electrons)

Daily Examples:

  • Rusting of iron (oxidation)
  • Bleaching (chlorine oxidizes colors)
  • Batteries (redox reactions)
  • Photosynthesis (CO₂ reduced to glucose)

3. ACIDS, BASES & SALTS

Acids:

  • Sour taste, pH < 7, turn blue litmus red
  • Strong: HCl, H₂SO₄, HNO₃
  • Weak: CH₃COOH (vinegar), citric acid

Bases:

  • Bitter taste, slippery, pH > 7, turn red litmus blue
  • Strong: NaOH, KOH
  • Weak: NH₄OH, Ca(OH)₂

Salts:

  • Neutralization product: Acid + Base → Salt + Water
  • Types: Normal (NaCl), Acidic (NaHSO₄), Basic (CaOCl₂)

pH Scale: 0–14

  • 0–6.9 → Acidic
  • 7 → Neutral
  • 7.1–14 → Basic

4. ATOMIC STRUCTURE

Atomic Models:

  • Dalton: Solid sphere
  • Thomson: Plum pudding
  • Rutherford: Nuclear model
  • Bohr: Planetary model
  • Quantum Mechanical: Electron clouds

Subatomic Particles:

Particle Charge Mass Location
Proton +1 1 amu Nucleus
Neutron 0 1 amu Nucleus
Electron −1 1/1836 amu Orbitals

Atomic Number (Z): Number of protons

Mass Number (A): Protons + Neutrons

Isotopes: Same Z, different A (¹²C, ¹³C, ¹⁴C)

5. PERIODIC CLASSIFICATION

  • Modern Periodic Law: Properties ∝ Atomic Number
  • Periods: 7 horizontal rows
  • Groups: 18 vertical columns

Group Characteristics:

  • Group 1 (Alkali metals): Very reactive, Na, K
  • Group 2 (Alkaline earth): Reactive, Ca, Mg
  • Group 17 (Halogens): Highly reactive, Cl, Br
  • Group 18 (Noble gases): Inert, He, Ne, Ar

Periodic Trends:

  • Atomic size: Decreases across period, increases down group
  • Ionization energy: Increases across, decreases down
  • Electronegativity: Increases across, decreases down

6. CHEMICAL BONDING

Types:

  • Ionic: Metal + Non-metal (NaCl)
  • Covalent: Non-metal + Non-metal (H₂O, CH₄)
  • Metallic: Metal atoms (Cu, Fe)
  • Hydrogen: Weak, in water, DNA

VSEPR Theory: Predicts molecular shapes

  • Linear, Trigonal planar, Tetrahedral, etc.

7. FUELS

Classification:

  • Solid: Coal, wood, charcoal
  • Liquid: Petrol, diesel, kerosene
  • Gaseous: LPG, CNG, biogas

Calorific Value (kJ/kg):

  • Hydrogen: 150,000 (highest)
  • Methane: 55,000
  • Petrol: 48,000
  • Coal: 25,000–30,000

Octane Number: Petrol quality (iso-octane = 100)

Cetane Number: Diesel quality (cetane = 100)

8. METALLURGY

Processes:

  • Concentration: Remove impurities (gangue)
  • Reduction: Extract metal from ore
  • Refining: Purify metal

Extraction Methods:

  • Iron: Blast furnace (Fe₂O₃ + CO → Fe)
  • Aluminum: Electrolysis of Al₂O₃ (Hall–Héroult)
  • Copper: Roasting then electrolysis

Alloys:

  • Steel: Fe + C (0.2–2%)
  • Stainless steel: Fe + Cr + Ni
  • Brass: Cu + Zn
  • Bronze: Cu + Sn

9. BEHAVIOR OF GASES

Gas Laws:

  • Boyle’s Law: P ∝ 1/V (constant T)
  • Charles’s Law: V ∝ T (constant P)
  • Avogadro’s Law: V ∝ n (constant P,T)
  • Ideal Gas Equation: PV = nRT

Diffusion:

  • Graham’s Law: Rate ∝ 1/√M
  • Light gases diffuse faster

10. ELECTROLYSIS

Process: Electric current → Chemical decomposition

Examples:

  • Water electrolysis: 2H₂O → 2H₂ + O₂
  • Electroplating: Chrome plating, gold plating
  • Metal extraction: Al from Al₂O₃
  • Rechargeable batteries

Faraday’s Laws:

  • Mass deposited ∝ Charge passed
  • For same charge, mass ∝ Equivalent weight

11. CARBON & ITS COMPOUNDS

Allotropes:

  • Diamond: Hardest, insulator
  • Graphite: Soft, conductor
  • Fullerenes: C60 (buckyballs)
  • Graphene: Single layer graphite

Organic Compounds:

  • Hydrocarbons: Alkanes (C–C single), Alkenes (C=C), Alkynes (C≡C)
  • Functional Groups: Alcohol (-OH), Carboxylic acid (-COOH), etc.

Isomerism: Same formula, different structures

12. NON-METALS

Important Non-Metals:

Element Properties Uses
Hydrogen Lightest, explosive Fuel, ammonia production
Oxygen Supports combustion Breathing, steel making
Nitrogen Inert atmosphere Fertilizers, explosives
Chlorine Greenish-yellow gas Water purification, PVC
Sulfur Yellow solid Sulfuric acid, vulcanization
Phosphorus White (stored in water) Matches, fertilizers
Carbon Forms many compounds Fuel, diamonds, organic chemistry

13. IMPORTANT FACTS ABOUT METALS

Metal Symbol Properties Uses
Sodium Na Soft, reacts with water Salt, street lights
Potassium K More reactive than Na Fertilizers, soaps
Calcium Ca Found in bones, teeth Cement, plaster
Aluminum Al Light, corrosion resistant Aircraft, utensils
Iron Fe Magnetic, rusts Construction, machinery
Copper Cu Good conductor Electrical wires, coins
Zinc Zn Anti-corrosive Galvanizing, batteries
Silver Ag Best conductor Jewelry, photography
Gold Au Inert, malleable Jewelry, electronics
Mercury Hg Liquid at room temp Thermometers, barometers

14. COMMON FACTS

  • Hardest substance: Diamond
  • Lightest metal: Lithium
  • Best conductor: Silver
  • Most abundant metal: Aluminum (Earth's crust)
  • Most abundant element: Oxygen (Earth's crust)
  • Most abundant in universe: Hydrogen
  • Liquid metals: Mercury, Gallium
  • Noble metals: Gold, Platinum (don't corrode)

1. INTRODUCTION

Characteristics of Living Organisms:

  • Growth, Reproduction, Metabolism, Response to stimuli
  • Homeostasis, Adaptation, Evolution

Levels of Organization:

  • Cell → Tissue → Organ → System → Organism

2. CLASSIFICATION OF ORGANISMS

Five Kingdom System (Whittaker):

  • Monera: Bacteria, cyanobacteria (prokaryotic)
  • Protista: Amoeba, Euglena (unicellular eukaryotic)
  • Fungi: Yeast, mushrooms (decomposers)
  • Plantae: Trees, flowers (autotrophs)
  • Animalia: Humans, animals (heterotrophs)

Binomial Nomenclature: Genus species (Homo sapiens)

3. NUTRIENTS

Macronutrients:

  • Carbohydrates: Energy (4 kcal/g)
  • Proteins: Growth, repair (4 kcal/g)
  • Fats: Energy storage (9 kcal/g)

Micronutrients:

  • Vitamins: A, B-complex, C, D, E, K
  • Minerals: Ca, Fe, I, Na, K, P

Balanced Diet Components:

  • 60–70% carbohydrates
  • 10–15% proteins
  • 20–30% fats
  • Vitamins, minerals, water, fiber

4. HUMAN DISEASES

Disease Cause Symptoms Prevention
Malaria Plasmodium parasite Fever, chills, sweating Mosquito control, nets
Tuberculosis Mycobacterium Cough, weight loss, fever BCG vaccine, hygiene
Cholera Vibrio cholerae Diarrhea, dehydration Clean water, sanitation
Diabetes Insulin deficiency Thirst, frequent urination Diet control, exercise
Hypertension High BP Headaches, dizziness Low salt, stress management
Arthritis Joint inflammation Pain, stiffness Exercise, weight control
Asthma Allergic reaction Breathing difficulty Avoid allergens
Cancer Uncontrolled cell growth Varies by type Healthy lifestyle, screening

5. ORGANIC EVOLUTION

Theories:

  • Lamarckism: Use and disuse, inheritance of acquired characters
  • Darwinism: Natural selection, survival of fittest
  • Modern Synthesis: Combines genetics with natural selection

Evidence:

  • Fossil records
  • Homologous organs (same structure, different function)
  • Analogous organs (different structure, same function)
  • Embryological similarities
  • Molecular biology (DNA similarities)

6. BOTANY

Plant Kingdom Classification:

  • Thallophyta: Algae (Spirogyra)
  • Bryophyta: Mosses (no vascular tissue)
  • Pteridophyta: Ferns (vascular, no seeds)
  • Gymnosperms: Pine, cycas (naked seeds)
  • Angiosperms: Flowering plants (seeds in fruit)
    • Monocots: One cotyledon (rice, wheat)
    • Dicots: Two cotyledons (gram, pea)

Plant Morphology:

  • Root: Anchorage, absorption (Taproot/Fibrous)
  • Stem: Support, transport (Herbaceous/Woody)
  • Leaf: Photosynthesis (Simple/_attachCompound)
  • Flower: Reproduction (Complete/Incomplete)
  • Fruit: Seed dispersal
  • Seed: Embryonic plant

Plant Hormones:

  • Auxins: Cell elongation (phototropism)
  • Gibberellins: Stem growth, seed germination
  • Cytokinins: Cell division
  • Abscisic Acid: Stress response, dormancy
  • Ethylene: Fruit ripening, leaf fall

Plant Diseases:

Disease Causal Organism Affected Crop Symptoms
Blast Fungus Rice Spots on leaves
Rust Fungus Wheat Orange pustules
Smut Fungus Cereals Black powder
Citrus Canker Bacteria Citrus fruits Lesions on leaves/fruits
TMV Virus Tobacco Mosaic pattern
Late Blight Fungus Potato Black spots, rot

Plant Tissue:

  • Meristematic: Dividing cells (apical, lateral, intercalary)
  • Permanent: Matured cells
    • Simple: Parenchyma, Collenchyma, Sclerenchyma
    • Complex: Xylem (water transport), Phloem (food transport)

Photosynthesis:

Equation: 6CO2 + 6H2O + light → C6H12O6 + 6O2

Process:

  • Light Reaction: Thylakoids → ATP + NADPH + O2
  • Dark Reaction (Calvin Cycle): Stroma → Glucose

Factors Affecting:

  • Light intensity, CO2 concentration, temperature, water

Ecology:

Levels: Organism → Population → Community → Ecosystem → Biome → Biosphere

Energy Flow: Sun → Producers → Consumers → Decomposers

Pollution:

  • Air: CO, SO2, NO2, particulate matter
  • Water: Industrial waste, sewage, pesticides
  • Soil: Plastics, chemicals, waste dumping
  • Noise: > 85 dB harmful
  • Thermal: Heated water from industries

7. ZOOLOGY

Animal Kingdom Classification:

Major Phyla:

  • Porifera: Sponges (pores)
  • Coelenterata: Jellyfish, corals (stinging cells)
  • Platyhelminthes: Flatworms (tapeworms)
  • Nematoda: Roundworms (Ascaris)
  • Annelida: Segmented worms (earthworm)
  • Arthropoda: Insects, spiders (jointed legs)
  • Mollusca: Snails, octopus (soft body)
  • Echinodermata: Starfish (spiny skin)
  • Chordata: Notochord present
    • Pisces: Fish
    • Amphibia: Frogs (dual life)
    • Reptilia: Snakes, lizards (scales)
    • Aves: Birds (feathers)
    • Mammalia: Humans, animals (mammary glands)

Animal Tissue:

  • Epithelial: Covering/lining (squamous, cuboidal, columnar)
  • Connective: Support/binding (bone, blood, cartilage)
  • Muscular: Movement (skeletal, cardiac, smooth)
  • Nervous: Impulse transmission (neurons, neuroglia)

8. HUMAN BLOOD

Components:

  • Plasma (55%): Water, proteins, nutrients, waste
  • Formed Elements (45%):
    • RBCs: 4.5–5.5 million/µL, carry O2 (hemoglobin)
    • WBCs: 6000–8000/µL, immunity (neutrophils, lymphocytes)
    • Platelets: 1.5–4 lakh/µL, clotting

Blood Groups:

ABO system + Rh factor

  • Universal Donor: O negative
  • Universal Recipient: AB positive

Functions:

  • Transport (O2, nutrients, waste, hormones)
  • Regulation (pH, temperature)
  • Protection (immunity, clotting)

9. CYTOLOGY (CELL BIOLOGY)

Cell Theory:

  • All living things made of cells
  • Cell is basic structural/functional unit
  • Cells arise from pre-existing cells

Cell Types:

  • Prokaryotic: No nucleus (bacteria)
  • Eukaryotic: True nucleus (plants, animals)

Cell Organelles:

Organelle Function
Nucleus Control center, contains DNA
Mitochondria Powerhouse, ATP production

Organelle Function
Ribosomes Protein synthesis
Endoplasmic Reticulum Transport, protein/lipid synthesis
Golgi Apparatus Processing, packaging
Lysosomes Digestion, waste removal
Chloroplasts Photosynthesis (plants only)
Cell Wall Protection, support (plants only)
Cell Membrane Selectively permeable barrier

Cell Division:

  • Mitosis: Somatic cells → 2 identical daughter cells
  • Meiosis: Germ cells → 4 haploid gametes

CELL MEMBRANE STRUCTURE

Fluid Mosaic Model (Singer & Nicolson):

  • Phospholipid bilayer with embedded proteins
  • Components:
    • Phospholipids: Hydrophilic heads, hydrophobic tails
    • Proteins: Integral (through) and Peripheral (surface)
    • Cholesterol: Provides stability
    • Carbohydrates: Cell recognition (glycoproteins, glycolipids)

Membrane Transport:

  • Passive: No energy required
    • Diffusion (O2, CO2)
    • Osmosis (Water)
    • Facilitated diffusion (Glucose via carriers)
  • Active: Energy (ATP) required
    • Sodium–Potassium Pump (3Na+ out, 2K+ in)
    • Proton pumps in plants

CELL ORGANELLES – DETAILED FUNCTIONS

Endoplasmic Reticulum:

  • Rough ER: Protein synthesis (ribosomes attached)
  • Smooth ER: Lipid synthesis, detoxification

Golgi Apparatus:

  • Modifies, sorts, packages proteins
  • Forms lysosomes, secretory vesicles

Peroxisomes:

  • Detoxify hydrogen peroxide (H2O2 → H2O + O2)
  • β-oxidation of fatty acids

CELL CYCLE & DIVISION

Interphase (90% of cycle):

  • G1 Phase: Cell growth
  • S Phase: DNA replication
  • G2 Phase: Preparation for division

Mitosis Stages:

  • Prophase: Chromosomes condense, nuclear envelope disappears
  • Metaphase: Chromosomes align at equator
  • Anaphase: Sister chromatids separate
  • Telophase: Nuclear envelopes reform
  • Cytokinesis: Cytoplasm divides

Meiosis Key Points:

  • Reduction division (diploid → haploid)
  • Meiosis I: Homologous chromosomes separate
  • Meiosis II: Sister chromatids separate
  • Crossing over in Prophase I → genetic variation

10. GENETICS

Mendel's Laws:

  • Law of Dominance: Dominant trait expressed
  • Law of Segregation: Alleles separate during gamete formation
  • Law of Independent Assortment: Genes for different traits assort independently

DNA Structure:

Double helix (Watson & Crick, 1953)

  • Nucleotides: A–T, G–C pairing

Genetic Disorders:

  • Down Syndrome: Trisomy 21
  • Hemophilia: Sex-linked recessive (clotting disorder)
  • Sickle Cell Anemia: Autosomal recessive (abnormal hemoglobin)
  • Color Blindness: X-linked recessive

DNA Replication:

Semi-Conservative (Meselson–Stahl experiment)

Enzymes Involved:

  • Helicase: Unwinds DNA
  • Primase: RNA primer synthesis
  • DNA Polymerase III: Adds nucleotides
  • DNA Polymerase I: Removes RNA primers
  • Ligase: Joins Okazaki fragments

PROTEIN SYNTHESIS

Transcription (DNA → mRNA):

  • RNA polymerase binds to promoter
  • Template strand used
  • mRNA processed (capping, tailing, splicing)

Translation (mRNA → Protein):

  • Ribosome: 70S (prokaryotes), 80S (eukaryotes)
  • Sites: A (aminoacyl), P (peptidyl), E (exit)
  • tRNA: Brings amino acids, has anticodon
  • Genetic Code: Triplet, universal, degenerate

GENETIC DISORDERS

Disorder Inheritance Defect Symptoms
Thalassemia Autosomal recessive Hemoglobin synthesis Anemia, bone deformities
Cystic Fibrosis Autosomal recessive Chloride channel (CFTR) Lung infections, digestive issues
Huntington's Autosomal dominant Huntingtin protein Uncontrolled movements, dementia
Phenylketonuria Autosomal recessive Phenylalanine hydroxylase Mental retardation, musty odor
Turner Syndrome Chromosomal (XO) Missing X chromosome Short stature, infertile, webbed neck
Klinefelter Syndrome Chromosomal (XXY) Extra X in males Tall, infertile, gynecomastia

HUMAN GENOME PROJECT

  • Completed: 2003
  • 3.2 billion base pairs
  • 20,000–25,000 genes
  • Applications: Disease diagnosis, gene therapy, pharmacogenomics

11. SYSTEMS OF HUMAN BODY

Digestive System:

  • Mouth → Esophagus → Stomach → Small Intestine → Large Intestine
  • Accessory organs: Liver, Pancreas, Gall bladder

Circulatory System:

  • Heart: 4 chambers (2 atria, 2 ventricles)
  • Blood vessels: Arteries, Veins, Capillaries

Respiratory System:

  • Nose → Pharynx → Larynx → Trachea → Bronchi → Lungs (alveoli)

Excretory System:

  • Kidneys → Ureters → Bladder → Urethra
  • Nephron: Functional unit of kidney

Nervous System:

  • Central: Brain, Spinal cord
  • Peripheral: Nerves
  • Autonomic: Sympathetic (fight/flight), Parasympathetic (rest/digest)

Endocrine System:

  • Hormone-producing glands
  • Pituitary, Thyroid, Adrenal, Pancreas, Gonads

Reproductive System:

  • Male: Testes → sperm production
  • Female: Ovaries → egg production, uterus → fetal development

Skeletal System:

  • 206 bones
  • Functions: Support, protection, movement, mineral storage

Muscular System:

  • Types: Skeletal (voluntary), Smooth (involuntary), Cardiac (heart)

Integumentary System:

  • Skin, hair, nails
  • Functions: Protection, temperature regulation, sensation

12. NEUROBIOLOGY

Neuron Structure:

  • Dendrites: Receive signals
  • Cell body: Contains nucleus
  • Axon: Transmits signals
  • Myelin sheath: Insulation (Schwann cells in PNS, Oligodendrocytes in CNS)
  • Nodes of Ranvier: Saltatory conduction

Synaptic Transmission:

  • Action potential reaches axon terminal
  • Ca2+ channels open
  • Neurotransmitter release (acetylcholine, dopamine, serotonin)
  • Binds to postsynaptic receptors
  • Postsynaptic potential generated

Reflex Action:

  • Components: Receptor → Sensory neuron → Spinal cord → Motor neuron → Effector
  • Examples: Knee jerk, blinking, withdrawal from pain

13. ENDOCRINE SYSTEM DETAILS

Major Hormones & Functions:

Gland Hormone Function Disorder (Excess/Deficiency)
Pituitary Growth Hormone (GH) Growth Gigantism/Dwarfism
Pituitary TSH Stimulates thyroid –
Thyroid Thyroxine (T4) Metabolic rate Goiter, Cretinism, Myxedema
Parathyroid PTH Calcium regulation Tetany/Osteoporosis
Pancreas Insulin Glucose uptake Diabetes
Pancreas Glucagon Glucose release Hypoglycemia
Adrenal Adrenaline Fight/flight –
Adrenal Cortisol Stress response Cushing's/Addison's
Gonads Testosterone / Estrogen Sex characteristics Infertility, hormonal imbalances

Feedback Mechanisms:

  • Negative: Hormone inhibits its own production (Insulin, Thyroxine)
  • Positive: Hormone stimulates its own production (Oxytocin during labor)

14. IMMUNE SYSTEM

Innate Immunity:

  • Physical barriers: Skin, mucous membranes
  • Cellular: Phagocytes (neutrophils, macrophages), Natural Killer cells
  • Chemical: Complement system, Interferons
  • Inflammatory response

Adaptive Immunity:

  • Humoral: B cells → Plasma cells → Antibodies
  • Cell-mediated: T cells (Helper, Cytotoxic, Memory)

Vaccination Types:

  • Live attenuated (MMR, BCG)
  • Inactivated/killed (Polio, Hepatitis A)
  • Subunit/recombinant (Hepatitis B)
  • Toxoid (Tetanus, Diphtheria)

Autoimmune Diseases:

  • Rheumatoid arthritis (joints)
  • Type 1 diabetes (pancreatic β-cells)
  • Multiple sclerosis (myelin sheath)
  • Lupus (multiple organs)

15. PLANT PHYSIOLOGY

MINERAL NUTRITION IN PLANTS

Essential Elements:

  • Macronutrients: N, P, K, Ca, Mg, S (required in large amounts)
  • Micronutrients: Fe, Mn, Zn, Cu, B, Mo, Cl (trace amounts)

Deficiency Symptoms:

  • Nitrogen: Chlorosis (yellowing), stunted growth
  • Potassium: Scorching of leaf margins
  • Phosphorus: Purple coloration, poor flowering
  • Magnesium: Interveinal chlorosis

TRANSPORT IN PLANTS

Water Transport:

  • Root pressure: Pushes water upward (guttation)
  • Cohesion–Tension Theory: Transpiration pull
  • Capillary action: Adhesion–cohesion

Food Transport:

  • Pressure Flow Hypothesis: Source (leaves) → Sink (roots/fruits)
  • Phloem loading/unloading

PLANT GROWTH REGULATORS (Expanded)

Auxins:

  • Natural: IAA (Indole-3-acetic acid)
  • Synthetic: 2,4-D (weedicide), NAA (rooting hormone)
  • Functions: Apical dominance, phototropism, fruit development

Gibberellins:

  • Stem elongation (bolting in cabbage)
  • Seed germination (breaks dormancy)
  • Fruit setting (seedless grapes)

Cytokinins:

  • Promotes cell division (found in coconut milk)
  • Delays senescence (aging)

Abscisic Acid (ABA):

  • Stress hormone (drought, cold)
  • Induces dormancy
  • Stomatal closure

Ethylene:

  • Gaseous hormone
  • Triple response (seedlings)
  • Fruit ripening (climacteric fruits)

PHOTOPERIODISM

  • Short Day Plants: Flower when day < critical length (rice, soybean)
  • Long Day Plants: Flower when day > critical length (wheat, radish)
  • Day Neutral Plants: Flower independent of day length (tomato, cucumber)

Vernalization: Cold treatment induces flowering (winter wheat)

16. REPRODUCTION BIOLOGY

HUMAN REPRODUCTIVE SYSTEM

Male:

  • Testes: Spermatogenesis (seminiferous tubules)
  • Epididymis: Sperm maturation and storage
  • Accessory glands: Prostate, seminal vesicles, bulbourethral glands
  • Semen: Sperm + secretions (fructose for energy, prostaglandins)

Female:

  • Ovaries: Oogenesis, hormone production
  • Menstrual cycle (28 days):
    • Follicular phase: FSH → follicle development → estrogen
    • Ovulation: LH surge (day 14)
    • Luteal phase: Corpus luteum → progesterone

Fertilization & Implantation:

  • Fertilization in fallopian tube (ampulla)
  • Zygote → Morula → Blastocyst
  • Implantation in endometrium (day 7)
  • Placenta formation (nutrient/waste exchange)

EMBRYONIC DEVELOPMENT

Germ Layers:

  • Ectoderm: Nervous system, epidermis
  • Mesoderm: Muscles, bones, circulatory system
  • Endoderm: Gut lining, liver, pancreas

Stages:

Cleavage → Blastulation → Gastrulation → Organogenesis

Twins:

  • Identical (Monozygotic): Single zygote splits, same genetic makeup
  • Fraternal (Dizygotic): Two eggs fertilized, different genetic makeup

17. BIOTECHNOLOGY

RECOMBINANT DNA TECHNOLOGY

Steps:

  • Isolation of DNA
  • Cutting with restriction enzymes (EcoRI, HindIII)
  • Ligation with DNA ligase
  • Insertion into vector (plasmid, bacteriophage)
  • Transformation into host (bacteria, yeast)
  • Selection of recombinants

Applications:

  • Medicine: Insulin, growth hormone, vaccines
  • Agriculture: Bt cotton, Golden rice (Vitamin A)
  • Industry: Enzymes (lipase in detergents)

PCR (Polymerase Chain Reaction)

  • Amplifies DNA exponentially
  • Steps: Denaturation → Annealing → Extension
  • Uses: DNA fingerprinting, disease diagnosis, forensics

DNA FINGERPRINTING

  • Developed by Alec Jeffreys
  • Uses VNTRs (Variable Number Tandem Repeats)
  • Applications: Paternity testing, criminal identification

STEM CELL TECHNOLOGY

Types:

  • Totipotent: Can form entire organism (zygote)
  • Pluripotent: Can form all cell types (embryonic stem cells)
  • Multipotent: Limited differentiation (adult stem cells)
  • iPSCs: Induced pluripotent stem cells (reprogrammed adult cells)

Applications: Regenerative medicine, disease modeling

CLONING

  • Reproductive cloning: Dolly the sheep (1996)
  • Therapeutic cloning: Embryonic stem cells for treatment
  • Gene cloning: Multiple copies of specific gene

18. ECOLOGY & ENVIRONMENT

POPULATION ECOLOGY

Population Growth Models:

  • Exponential: J-shaped curve (ideal conditions)
  • Logistic: S-shaped curve (carrying capacity limits)

Population Interactions:

Interaction Species A Species B Example
Mutualism + + Lichen (algae + fungus), Rhizobium + legumes
Commensalism + 0 Barnacles on whales, orchids on trees
Parasitism + − Tapeworm in human, Cuscuta on plants
Predation + − Lion–deer, insectivorous plants
Competition − − Trees for light, animals for territory

Succession:

  • Primary: Bare rock → soil formation → climax community
  • Secondary: Disturbed area → recovery (faster due to soil)

BIODIVERSITY & CONSERVATION

Hotspots in India:

  • Western Ghats
  • Eastern Himalayas
  • Indo-Burma region

Conservation Methods:

  • In-situ: Protected areas (national parks, sanctuaries)
  • Ex-situ: Zoos, botanical gardens, seed banks

Threats to Biodiversity:

  • Habitat loss (major cause)
  • Overexploitation
  • Invasive species
  • Pollution
  • Climate change

Keystone Species: Species with disproportionate effect on ecosystem (Sea otter, Fig tree)

19.ENVIRONMENTAL ISSUES

Eutrophication:

  • Excess nutrients → Algal bloom → Oxygen depletion → Dead zones

Biomagnification:

  • DDT, mercury accumulate up food chain
  • Top predators most affected

Ozone Depletion:

  • CFCs destroy ozone layer
  • Montreal Protocol (1987) to phase out CFCs

Acid Rain:

  • SO₂, NO₂ → H₂SO₄, HNO₃
  • Damages buildings, aquatic life, forests

20. HEALTH & DISEASES

COMMUNICABLE DISEASES

Disease Pathogen Vector/Transmission Symptoms
Dengue Dengue virus Aedes mosquito High fever, rash, joint pain
Chikungunya Chikungunya virus Aedes mosquito Fever, severe joint pain

Disease Pathogen Vector/Transmission Symptoms
Japanese encephalitis Virus Culex mosquito Headache, seizures, paralysis
Leptospirosis Leptospira bacteria Water/soil contaminated with urine Fever, muscle pain, kidney damage
Rabies Rabies virus Dog bite Hydrophobia, paralysis, death
Hepatitis Hepatitis virus Water/food, blood Jaundice, liver damage

NON-COMMUNICABLE DISEASES

Cardiovascular Diseases:

  • Atherosclerosis: Plaque in arteries
  • Myocardial infarction: Heart attack
  • Stroke: Brain blood vessel blockage/rupture

Cancer:

  • Carcinogens: Tobacco, UV radiation, chemicals
  • Oncogenes: Cancer-causing genes
  • Metastasis: Spread to other body parts
  • Treatment: Surgery, chemotherapy, radiotherapy, immunotherapy

Mental Health Disorders:

  • Depression, Anxiety disorders, Bipolar disorder
  • Schizophrenia, Alzheimer’s disease, Parkinson’s disease

NUTRITIONAL DISORDERS

Protein Energy Malnutrition (PEM):

  • Kwashiorkor: Protein deficiency (edema, pot belly)
  • Marasmus: Overall calorie deficiency (wasting)

Obesity:

  • BMI > 30 kg/m²
  • Health risks: Diabetes, hypertension, heart disease

Eating Disorders:

  • Anorexia nervosa: Self-starvation
  • Bulimia nervosa: Binge eating followed by purging

21. BIOLOGICAL TECHNIQUES & INSTRUMENTS

MICROSCOPY

Types:

  • Light Microscope: Up to 2000× magnification
  • Electron Microscope:
    • TEM: Internal structure (up to 10,00,000×)
    • SEM: Surface structure (3D images)

Staining Techniques:

  • Gram staining: Bacteria classification (Gram +ve/−ve)
  • Giemsa staining: Chromosomes, malaria parasite
  • Acetocarmine: Chromosome staining

CENTRIFUGATION

  • Separates components by density
  • Differential: Organelle separation
  • Ultracentrifugation: Macromolecules, viruses

CHROMATOGRAPHY

  • Separates mixtures
  • Paper chromatography: Plant pigments
  • Column chromatography: Protein purification
  • HPLC: High-performance liquid chromatography

ELECTROPHORESIS

  • Separates charged molecules in electric field
  • Agarose gel: DNA fragments
  • Polyacrylamide gel: Proteins (SDS-PAGE)

SPECTROPHOTOMETRY

  • Measures light absorption
  • Determines concentration (Beer–Lambert law)
  • Applications: DNA quantification, enzyme assays

22. RECENT ADVANCES IN BIOLOGY

CRISPR–Cas9

  • Gene editing technology
  • Bacterial immune system adapted
  • Applications: Gene therapy, agriculture, research

ORGAN TRANSPLANTATION

  • First successful: Kidney (1954)
  • Immunosuppressants: Prevent organ rejection
  • Organ donation types: Live, deceased, tissue

ARTIFICIAL ORGANS

  • Pacemaker (heart)
  • Dialysis machine (kidney)
  • Cochlear implants (ear)
  • Bionic limbs

3D BIOPRINTING

  • Creates tissues/organs using living cells
  • Potential for organ transplantation without donors

SYNTHETIC BIOLOGY

  • Designing new biological systems
  • Artificial genomes
  • Biofuels, biosensors