Examination Scheme

There will be one paper of two hours duration of 80 marks and Internal Assessment of practical work carrying 20 marks.

• The paper will be divided into two sections:
  • Section I (40 marks, compulsory): Short answer questions on the entire syllabus.
  • Section II (40 marks): Six questions. Candidates must answer any four.

1. Basic Biology

1. Cell Cycle and Cell Division
   • Cell cycle – Interphase (G₁, S, G₂) and Mitotic phase.
   • Cell Division:
     • Mitosis and its stages.
     • Basic understanding of Meiosis as a reduction division (stages not required).
     • Homologous chromosomes and crossing over leading to variations (brief idea).
     • Significance and major differences between mitotic and meiotic division.
2. Structure of Chromosome
   • Basic structure; terms: chromatin, chromatid, gene structure of DNA, centromere.
3. Genetics: Mendel’s Laws and Sex-linked Inheritance
   • The three laws of Mendel.
   • Monohybrid cross – phenotype and genotype.
   • Dihybrid cross – Only phenotype.
   • Terms: gene, allele, heterozygous, homozygous, dominant, recessive, mutation, variation, phenotype, genotype.
   • Sex determination in human beings. X-linked diseases: haemophilia, colour blindness.

2. Plant Physiology

1. Absorption by Roots
   • Imbibition, diffusion, osmosis; osmotic pressure, root pressure; turgidity, flaccidity, plasmolysis, deplasmolysis.
   • Active & passive transport; rise of water up to xylem; ascent of sap.
   • Processes related to absorption of water by roots.
   • Root characteristics for water absorption, root hair structure.
   • Cohesive, adhesive forces, transpirational pull.
   • Experiments showing conduction of water through xylem.
2. Transpiration
   • Process, significance.
   • Ganong’s potometer; limitations; factors affecting rate; related experiments.
   • Guttation and bleeding (brief idea).
   • Mechanism of stomatal transpiration (potassium ion exchange theory).
   • Adaptations to reduce transpiration.
   • Experiments:
     • Weight loss of plant/leafy shoot by transpiration.
     • Cobalt chloride paper for unequal transpiration (dorsiventral leaf).
3. Photosynthesis
   • Process and significance.
   • Internal structure of chloroplast (site of light/dark reactions).
   • Stomata opening/closing (potassium ion exchange theory).
   • Overall balanced equation; "photochemical" and "biosynthetic" phases.
   • Light reaction: activation of chlorophyll, photolysis of water, O₂ release, ATP & NADPH formation.
   • Dark reaction: formation of glucose (details not required).
   • Adaptations for photosynthesis.
   • Experiments: factors essential for photosynthesis, destarching, starch test steps.
   • Diagram of the carbon cycle.
4. Chemical Coordination in Plants
   • Plant growth regulators: Auxins, Gibberellins, Cytokinins, Abscisic acid, Ethylene (effects).
   • Tropic movements: Phototropism, Geotropism, Hydrotropism, Thigmotropism, Chemotropism (with examples).

3. Human Anatomy and Physiology

1. Circulatory System
   • Blood and lymph; structure & working of heart; main blood vessels (heart, liver, kidney); lymphatic system.
   • RBC, WBC, platelets; tissue fluid and lymph.
   • Efficiency of mammalian RBC (absence of organelles).
   • Blood coagulation (brief).
   • Heart structure, working; concept of systole, diastole, double circulation; pulse, blood pressure.
   • Blood vessels: artery, vein, capillary (diagrams, structure-function relationship).
   • Lymphatic organs: spleen, tonsils (brief).
   • ABO blood group system, Rh factor.
   • Hepatic portal system (significance).
2. Excretory System
   • Excretory organs overview.
   • External and internal kidney structure; urinary system parts & vessels.
   • Functions (diagram with correct labelling); structure of nephron/kidney tubule.
   • Ultra-filtration (emphasis on malpighian capsule diagram), selective reabsorption, tubular secretion.
3. Nervous System
   • Neuron structure; central, autonomic, peripheral nervous systems (brief); brain, spinal cord, reflex/voluntary actions.
   • Parts of neuron, brain (Medulla Oblongata, Cerebrum, Cerebellum, Thalamus, Hypothalamus, Pons—functions).
   • White/gray matter distribution (brain, spinal cord).
   • Voluntary/involuntary actions (examples).
   • Reflex arc pathway diagram.
   • Functions: peripheral/autonomic NS (body activities regulation).
   • Difference: natural/acquired reflex.
   • Eye and Ear: structures (internal, external), functions, vision, adaptation, accommodation; eye defects (myopia, hyperopia, hypermetropia, presbyopia, astigmatism, cataract – diagrams for myopia, hyperopia only), corrective measures; hearing process, ear's role in balance.
4. Endocrine System
   • Study of: Adrenal, Pancreas, Thyroid, Pituitary; endocrine/exocrine glands (differences).
   • Location, shape of endocrine glands.
   • Hormones:
     • Pancreas: insulin, glucagon
     • Thyroid: thyroxin
     • Adrenal: cortical hormones, adrenaline
     • Pituitary: growth hormone, tropic hormones, ADH, oxytocin
   • Effects: hypo/hypersecretion
   • Feedback mechanism (TSH reference).
5. The Reproductive System
   • Organs, fertilisation, placenta functions (growth of embryo), menstrual cycle.
   • Functions: male/female organs, male accessory glands; secondary sexual characters.
   • Sperm & egg structure/functions.
   • Terms: fertilization, implantation, placenta, gestation, parturition.
   • Placenta's role: nutrition, respiration, excretion for embryo, endocrine function.
   • Foetal membranes, amniotic fluid functions.
   • Outline of menstrual cycle.
   • Sex hormones: testosterone, oestrogen, progesterone (in reproduction).
   • Identical/fraternal twins: meaning, differences only.

4. Population

• Population explosion in India, need for control measures.
• Main reasons for the sharp rise in human population in India/world.
• Terms: demography, population density, birth rate, death rate, growth rate.
• Problems due to explosion: unemployment, resource over-exploitation, low per capita income, price rise, pollution, wealth inequality.
• Control methods: Surgical – Tubectomy, Vasectomy.

5. Human Evolution

• Basic intro; Theories: Lamarck’s theory of inheritance, Darwin’s theory of natural selection.
• Human ancestors (brief): Australopithecus, Homo habilis, H. erectus, Neanderthals, Cro-Magnon, Homo sapiens sapiens.
  • Bipedalism
  • Increasing cranial capacity
  • Reduction of canine teeth size
  • Forehead/brow ridges
  • Chin development
  • Body hair reduction
  • Height and posture
• Lamarck’s theory: use/disuse of organs (e.g., giraffe’s neck, vestigial organs in humans).
• Darwin’s theory: natural selection (peppered moth as example).

6. Pollution

1. Types and sources; major pollutants
   • Air: Vehicular, industrial emissions, burning garbage, brick kilns.
   • Water: Detergents, sewage, industrial waste, oil spills.
   • Thermal pollution.
   • Soil: Industrial/urban/domestic waste, chemical fertilizers.
   • Biomedical waste: used needles, syringes, soiled dressings.
   • Radiation: X-rays, fallout from nuclear plants.
   • Noise: Vehicles, industries, construction, loudspeakers.
2. Biodegradable and Non-biodegradable wastes
   • Biodegradable: e.g., paper, vegetable peels.
   • Non-biodegradable: e.g., plastics, glass, Styrofoam; pesticides like DDT, etc.
3. Effects & Control Measures
   • Effects on climate/environment/health/organisms; explanation of:
     • Greenhouse effect & global warming
     • Acid rain
     • Ozone layer depletion
   • Control measures:
     • Use of unleaded petrol/CNG
     • Engines off at signals
     • Social forestry
     • Sewage treatment plants
     • Ban on polythene/plastics
     • Organic farming
     • Euro Bharat vehicular standards
     Brief idea of above measures
   • Swachh Bharat Abhiyan – national clean India campaign (brief mention).

INTERNAL ASSESSMENT OF PRACTICAL WORK

The practical work is designed to test the candidates' observation skills using plant and animal specimens.

PLANT LIFE

• Observe permanent slides of mitosis stages.
• Experiments:
  • Diffusion: Potassium permanganate in water.
  • Osmosis: Thistle Funnel experiment; potato osmoscope.
  • Absorption: Small herbaceous plant.
• Transpiration:
  • Bell Jar demonstration.
  • Unequal transpiration (dorsiventral leaf, cobalt chloride paper).
  • Uptake of water & transpiration rate using Ganong’s potometer.
• Photosynthesis:
  • Necessity of light, CO₂, chlorophyll (experiments).
  • Release of O₂ during photosynthesis (hydrilla/elodea).

ANIMAL LIFE

• Identify urinary system structures/heart/kidney (internal) and brain (external) via models/charts.
• Identify blood cells under a microscope.
• Identify internal structure of eye/ear (models/charts).
• Identify and locate endocrine glands: adrenal, pancreas, thyroid, pituitary (models/charts).

Evaluation

• Practical/project work evaluated by subject teacher and External Examiner (not teaching subject in relevant class/section).
• Internal Examiner and External Examiner assess independently.

  Examiner	Marks
  Subject Teacher (Internal Examiner)	10
  External Examiner	10

• Total marks (out of 20) sent to Council by Head of school (responsible for online entry via CAREERS portal).

INTERNAL ASSESSMENT IN SCIENCE - GUIDELINES FOR MARKING WITH GRADES