ICSE Class 10 Biology Syllabus 2026-27 — Complete Guide with 15 Chapters & Tips

What's New in 2026-27?

The ICSE Class 10 Biology syllabus for 2026-27 covers 15 chapters spanning cell biology, genetics, plant and human physiology, ecology, and human evolution. CISCE continues to emphasise diagram-based questions, application of biological concepts to real-world health and environmental issues, and competency-based questions that test analytical thinking beyond textbook recall.

Biology (Science Paper 3) carries 80 marks for the theory examination and 20 marks for Internal Assessment (practical work). Duration: 2 hours.

Syllabus Overview

Chapter No.	Chapter Name	Key Topics
1	Cell Cycle and Cell Division	Mitosis, meiosis, stages, significance
2	Genetics	Mendel's laws, monohybrid/dihybrid cross, sex determination
3	Absorption by Roots	Osmosis, diffusion, active transport, root hair structure
4	Transpiration	Process, factors, significance, experiments
5	Photosynthesis	Light and dark reactions, factors, experiments
6	Chemical Coordination in Plants	Auxins, gibberellins, tropisms
7	The Circulatory System	Heart, blood vessels, blood composition, circulation
8	The Excretory System	Nephron, urine formation, kidney structure
9	The Nervous System	CNS, PNS, reflex arc, brain structure
10	Sense Organs — The Eye	Structure, defects, corrective measures
11	The Endocrine System	Glands, hormones, functions, disorders
12	The Reproductive System	Male/female reproductive organs, fertilisation, menstrual cycle
13	Population	Population explosion, birth/death rate, demographic transition
14	Pollution	Air, water, soil pollution — causes, effects, prevention
15	Human Evolution	Evidences, stages, Homo sapiens development

Chapter-wise Detailed Syllabus

1. Cell Cycle and Cell Division

The cell cycle — interphase (G1, S, G2) and mitotic phase. Mitosis: Stages (prophase, metaphase, anaphase, telophase), cytokinesis, significance (growth, repair). Meiosis: Meiosis I (reductional) and Meiosis II (equational), crossing over, significance (genetic variation, gamete formation). Comparison of mitosis and meiosis.

2. Genetics

Mendel's Laws: Law of Dominance, Law of Segregation, Law of Independent Assortment. Monohybrid cross (3:1 ratio), dihybrid cross (9:3:3:1 ratio), test cross, back cross. Sex Determination: XX-XY mechanism in humans, sex-linked inheritance. Basic concepts of DNA and genes.

3. Absorption by Roots

Structure of root hair. Osmosis — endosmosis and exosmosis, plasmolysis, deplasmolysis. Diffusion. Active transport. Absorption of water and minerals by roots. Role of root pressure in water uptake.

4. Transpiration

Definition, types (stomatal, cuticular, lenticular). Structure and functioning of stomata. Factors affecting transpiration (light, temperature, humidity, wind). Significance of transpiration. Experiments: ganong's potometer, cobalt chloride paper test.

5. Photosynthesis

Definition, overall equation, site of photosynthesis (chloroplast structure). Light reaction and dark reaction (Calvin cycle — basic understanding). Factors affecting photosynthesis (light, CO₂, temperature, water). Experiments to test for starch, necessity of light, CO₂, and chlorophyll.

6. Chemical Coordination in Plants

Plant hormones — auxins, gibberellins, cytokinins, abscisic acid, ethylene. Tropisms — phototropism, geotropism, hydrotropism, thigmotropism. Role of auxin in phototropism. Practical applications of plant hormones.

7. The Circulatory System

Structure of the human heart (4 chambers), blood vessels (arteries, veins, capillaries). Double circulation — pulmonary and systemic. Blood composition — RBC, WBC, platelets, plasma. Blood groups (ABO system, Rh factor). Lymphatic system basics.

8. The Excretory System

Structure of the kidney (cortex, medulla, pelvis). Structure of the nephron (Bowman's capsule, PCT, loop of Henle, DCT, collecting duct). Urine formation — glomerular filtration, selective reabsorption, tubular secretion. Dialysis and kidney transplant.

9. The Nervous System

Central Nervous System (brain, spinal cord) and Peripheral Nervous System. Structure of a neuron. Synapse and synaptic transmission. Reflex action and reflex arc. Structure of the brain — cerebrum, cerebellum, medulla oblongata. Voluntary and involuntary actions.

10. Sense Organs — The Eye

Structure of the human eye (cornea, iris, pupil, lens, retina, optic nerve). Image formation. Accommodation — near point and far point. Defects of vision — myopia, hypermetropia, astigmatism, presbyopia. Corrective measures (concave/convex lenses). Comparison with a camera.

11. The Endocrine System

Endocrine glands — pituitary, thyroid, parathyroid, adrenal, pancreas (islets of Langerhans), gonads. Hormones — functions, target organs, disorders (diabetes, goitre, dwarfism, gigantism, Addison's disease). Comparison of nervous and endocrine systems.

12. The Reproductive System

Male reproductive system — testes, vas deferens, urethra, accessory glands. Female reproductive system — ovaries, fallopian tubes, uterus, vagina. Menstrual cycle (28 days), fertilisation, implantation. Basics of fetal development. Population control methods.

13. Population

Population explosion — causes and consequences. Birth rate, death rate, growth rate. Demographic transition. Population control measures. Impact of population growth on resources and environment.

14. Pollution

Air pollution — causes (vehicular, industrial), effects (acid rain, global warming, ozone depletion), prevention. Water pollution — causes, effects, BOD. Soil pollution — pesticides, industrial waste. Noise pollution. Biodegradable and non-biodegradable waste.

15. Human Evolution

Evidences of evolution — fossils, comparative anatomy, embryology. Timeline: Dryopithecus → Ramapithecus → Australopithecus → Homo habilis → Homo erectus → Homo sapiens neanderthalensis → Homo sapiens sapiens. Characteristics of each stage.

Exam Pattern 2026-27

Component	Details	Marks
Section I	Compulsory short-answer questions from all chapters	40 marks
Section II	Answer 4 out of 6 structured/long-answer questions	40 marks
Internal Assessment	Practical work, project, periodic tests	20 marks
Total		100 marks

Prescribed Textbooks

• Concise Biology Class 10 — Selina Publishers (K.K. Gupta)
• ICSE Biology for Class X — S. Chand Publishers
• Frank ISC Biology — Frank Brothers (supplementary reference)
• CISCE specimen papers and previous years' board papers

Preparation Tips

1. Master diagrams — Biology is a diagram-heavy subject. Practise drawing and labelling the heart, nephron, neuron, eye, brain, and reproductive organs. Neat diagrams score well.
2. Create comparison tables — Mitosis vs. meiosis, arteries vs. veins, CNS vs. PNS, endocrine vs. nervous system. Comparison questions are frequently asked.
3. Learn genetics problems — Practise monohybrid and dihybrid crosses until you can write Punnett squares from memory. Sex determination questions are almost always asked.
4. Understand experiments — Know the procedure, apparatus, observation, and conclusion for photosynthesis and transpiration experiments. Draw labelled diagrams of experimental setups.
5. Revise hormones systematically — Create a chart: gland → hormone → function → disorder. The endocrine system is a high-scoring chapter with predictable questions.
6. Focus on physiology chapters — Circulatory, excretory, and nervous systems carry high marks. Understand the process flow (e.g., blood circulation pathway, urine formation steps).
7. Don't neglect ecology chapters — Population and Pollution are shorter chapters but carry guaranteed marks. Revise them thoroughly in the last week.