ISC Class 11 Biology Syllabus 2026-27
CISCE has released the ISC Class 11 Biology Syllabus 2026-27 for the academic session. You can download the latest syllabus PDF from the official CISCE website under the Regulations and Syllabuses (ISC 2028) section.
The ISC Class 11 Biology Syllabus defines the course structure, unit-wise topics, practical work, and marks distribution. Students must follow this syllabus to prepare in a clear and structured way for the ISC Board exams.
The syllabus includes key topics such as Cell Structure, Plant Physiology, Human Physiology, and Diversity of Living Organisms. It also explains the exam pattern and internal assessment structure.
CISCE may update topics or question patterns for each session. Students should refer to the latest syllabus before starting preparation to stay aligned with the current exam pattern.
Oswal Publishers updates its ISC Class 11 Biology books based on the latest CISCE syllabus and paper pattern. These books support students with clear explanations and exam-focused questions.
You can download the ISC Class 11 Biology Syllabus 2026-27 PDF from the link below. Click on the “Download Now” button to access the official syllabus.
ISC Biology Class 11 Latest Syllabus 2026-27
There will be two papers in the subject:
Paper I: Theory: 3 hours ...70 marks
Paper II: Practical: 3 hours ... 15 marks
Project Work … 10 marks
Practical File … 5 marks
Paper 1- Theory: 70 Marks
| S. NO. | UNIT | TOTAL WEIGHTAGE |
| 1. | Diversity of Living Organisms | 09 Marks |
| 2. | Structural Organisation in Animals and Plants | 11 Marks |
| 3. | Cell: Structure and Function | 15 Marks |
| 4. | Plant Physiology | 17 Marks |
| 5. | Human Physiology | 18 Marks |
| TOTAL | 70 Marks | |
Paper I - theory - 70 Marks
Note: All structures (internal and external) are required to be taught along with diagrams.
1. Diversity of Living Organisms
(i) The Living World
Need for classification; taxonomy and systematics; concept of species and taxonomical hierarchy; binomial nomenclature.
Need for classification should be discussed. Definition and explanation of the terms
taxonomy (numerical taxonomy, cytotaxonomy and chemotaxonomy) and systematics. Concept of species. Major taxonomical hierarchies (phylum, class, order, family, genus, species): definition and examples with reference to classification of man, house fly, mango and wheat. Rules of binomial nomenclature and advantages of using scientific names.
Three systems of classification – artificial, natural and phylogenetic.
(ii) Biological Classification
Three domains of life; Five kingdom classification; s alient features and classification of Monera, Protista, Fungi, Plantae and Animalia. Lichens, Viruses, Viroids and Prions.
(a) Three domains of life – distinguishing features of (archaea, bacteria, eukarya).
Five-kingdom system of classification and characteristics of different kingdoms with
examples.
(b) Kingdom Monera: Bacteria - General structure of a typical bacterial cell; classification of bacteria according to shape, nutrition and mode of respiration; differences between gram +ve and gram –ve bacteria; types of reproduction – definition of fission, conjugation,
transduction and transformation (details not required).
A brief idea of the role of different types of archaebacteria (methanogens, halophiles and thermoacidophiles in their extreme environments).
Mycoplasma – three distinctive features.
Economic importance with reference to role of bacteria in sewage treatment, antibiotics, energy production and house hold products (curd and cheese only).
(c) Kingdom Protista – only two general characteristics and two examples of subgroups: (i) Chrysophytes (ii) Dinoflagellates, (iii) Euglenoids, (iv) Slime moulds, (v) Protozoans (to be
studied under rhizopods, flagellates, ciliates and sporozoans with two characteristics including modes of locomotion and two examples of each).
(d) Kingdom Fungi: general characteristics and mode of reproduction of each (including types of spores and sexual reproduction – definition of isogamy, anisogamy, oogamy, plasmogamy, karyogamy and dikaryophase). Zygomycetes, Ascomycetes, Basidiomycetes, Deuteromycetes - characteristics with examples. Role of fungi in the field of medicine, bakery and environmental decomposition. Definition of lichens and mycorrhiza (ecto and endo).
Life cycles not required.
(e) Virus (characteristic features – link between living and non-living, structure of TMV and bacteriophage and contribution of the following scientists: D.J. Ivanowsky, M.W. Beijerinck, W.M. Stanley). Definitions of Viroid and Prions (examples of the diseases caused by
prions – BSE and CJD).
(iii) Plant Kingdom
(a) Algae - characteristics (morphology, common name, major pigments, stored food, composition of cell wall, flagellar number and position of insertion, habitat, mode of sexual reproduction) and examples of Chlorophyceae, Phaeophyceae, Rhodophyceae; Economic importance of algae – any five.
(b) Bryophyta – general characteristics, distinctive features of liverworts and mosses; graphic outline of life cycle of Funaria with reference to alternation of generations. Economic importance of
bryophytes.
(c) Pteridophyta: characteristics; classification into classes: psilopsida (Psilotum), lycopsida (Selaginella, Lycopodium), sphenopsida (Equisetum) and pteropsida (Dryopteris, Pteris and Adiantum). Graphic outline of life cycle of a typical pteridophyte (fern). Definition of homospory and heterospory with relevant examples. Economic importance.
(d) Gymnosperms: general characteristics and graphic outline of life cycle of a typical gymnosperm (Pinus). Economic importance.
(iv) Animal Kingdom
Animal Kingdom: levels of organisation – (cellular level, tissue level, organ level, organ
system level); body plan (cell aggregate plan, blind-sac plan and tube-within-tube plan),
symmetry (spherical, radial and bilateral symmetry), (diploblastic and triploblastic
organisation in animals, coelom development- (acoelomate, seudocoelomate, coelomate and haemocoelomate), segmentation.
Non-chordata - five distinguishing characters with two examples of Porifera, Cnidaria, Ctenophora, Platyhelminthes, Nematoda (Aschelminthes), Annelida, Mollusca, Arthropoda, Echinodermata, Hemichordata.
Chordata – sub-classification of Chordata with reference to notochord - sub phyla Urochordata, ephalochordata. Vertebrata (classes – cyclostomata, chondrichthyes,
osteichthyes, amphibia, reptilia, aves and mammalia) – three distinguishing characters
with two examples of each).
2. Structural Organisation in Animals and Plants
(i) Morphology of Flowering Plants
(a) Morphology and modifications of root, stem, leaf.
Types of roots (tap, fibrous, adventitious), regions, modifications of roots for storage (Tuberous – e.g. Mirabilis and sweet potato; fusiform – e.g. radish; conical – e.g., carrot; napiform – e.g. turnip), respiration (pneumatophores) and support (stilt and prop).
Stems – features (nodes internodes, buds), modifications – underground (tuber, rhizome, corm) aerial (tendril, thorn, Phylloclade, cladode) and sub-aerial (runner, sucker, stolon, offset).
Leaves - parts of a simple leaf, venation, types of leaves (simple and compound – pinnate and palmate), phyllotaxy – alternate, opposite, whorled (with an example of each). Modifications for mechanical support (tendril), protection (spine), storage (bulb), reproduction (Bryophyllum); insectivorous plants (pitcher plant, Venus-fly-trap).
(b) Morphology of flower. Structure of a typical flower, types of inflorescence (racemose and cymose).
Structure of a typical flower, bracteates/ebracteate, [symmetry (actinomorphic, zygomorphic), trimerous/tetramerous/pentamerous complete/ incomplete, non-essential whorls (calyx: gamosepalous, polysepalous, corolla: gamopetalous, polysepalous, perianth, aestivation: valvate, twisted, imbricate, vexillary), essential whorls (androecium: cohesion - syngenesious, synandrous, monadelphous, diadelphous, polyadelphous; adhesion – epipetalous, epiphyllous; number of lobes – monothecous, dithecous; Gynoecium:
position of ovary – epigynous, hypogynous, perigynous, cohesion – apocarpous, syncarpous, number of locules – unilocular, bilocular, multilocular, placentation – axile, marginal, parietal, free central, basal; types of inflorescence (racemose and cymose – definition, examples, and differences; subtypes not required).
(ii) Anatomy of Flowering Plants
Plant Tissues: types of plant tissues: Meristematic tissues: classification of meristematic tissue. Permanent Tissues: structure and function of simple tissues (parenchyma, collenchyma and sclerenchyma) and complex tissues (xylem and phloem), tissue system. Internal structure of root, stem, and leaf.
Characteristics of meristematic tissue; classification of meristems based on origin and location; structure, function and location of permanent tissues; simple and complex tissues; epidermal, ground and vascular tissue systems.
Cellular diagrams of T.S. of roots and stem and V.S. of monocot and dicot leaves are
required.
(iii) Structural Organisation in Animals: Frog
Morphology, anatomy and functions of different systems (digestive, circulatory, respiratory, excretory, nervous and reproductive) of frog a brief account only.
3. Cell: Structure and Function
(i) Cell - the Unit of Life
Cell theory and cell as the basic unit of life: Structure of eukaryotic cells; Plant cell and
animal cell; cell envelope; cell membrane, cell wall; cell organelles – ultrastructure
and function; endomembrane system, mitochondria, ribosomes, plastids, microbodies; cytoskeleton, cilia, flagella, centrioles; nucleus.
Historical aspects, cell theory, size and shape of cells.
General structure of eukaryotic cell, ultra-
structure and function of cell wall (including
definition of plasmodesmata), cell membrane (description of fluid mosaic model; functions of the plasma membrane: active and passive transport, brief explanation of facilitated diffusion (uniport, symport and antiport) with one example]. Mitochondria, nucleus (nuclear membrane,
chromatin, nucleolus, structure and types of chromosomes on the basis of the position of centromere, satellite), types of plastids, endomembrane system (endoplasmic reticulum, Golgi complex, lysosomes and vacuoles), ribosomes, microbodies, cytoskeleton (microfilaments, microtubules and intermediate filaments), cilia, flagella and centrioles; differences between
prokaryotic cell and eukaryotic cell, plant cell and animal cell.
(ii) Biomolecules
Proteins, carbohydrates, lipids, enzymes, secondary metabolites.
Carbohydrates: general classification and functions of: monosaccharides (glucose, ribose and deoxyribose), disaccharides (maltose, lactose and sucrose), polysaccharides (glycogen, starch, cellulose, inulin, and chitin).
Proteins: amino acids – (structure: glycine, alanine, serine); amino acids as zwitter-ion;
examples of acidic, basic, neutral, sulphur
containing amino acids; essential and non- essential amino acids; levels of protein
structure (primary, secondary, tertiary and quaternary); functions of proteins.
Lipids: classification, structure and functions of fats and oils.
Enzymes: general properties, nomenclature and classification of enzymes according to
type of reactions, co-factors (prosthetic groups, coenzymes and metal ions). Factors
affecting enzyme activity - temperature, pH, substrate concentration. Competitive
inhibitors.
Definition and examples of secondary metabolites.
(iii) Cell Cycle and Cell Division
Cell cycle, mitosis, meiosis and their significance.
Definition of C-value, different stages of cell cycle (Go, G1, S and G2 and M).
Different stages of mitosis and meiosis (prophase – I) with diagrams. Significance of
mitosis and meiosis. Differences between mitosis and meiosis.
4. Plant Physiology
(i) Photosynthesis in higher plants
Photosynthesis as a mean of autotrophic nutrition; site of photosynthesis, pigments involved in photosynthesis (elementary idea); photochemical and biosynthetic phases of photosynthesis; cyclic and non-cyclic photophosphorylation; chemiosmotic hypothesis; photorespiration; C3 and C4 pathways; factors affecting photosynthesis.
Differences between absorption and action spectra.
Brief idea of photosynthetic pigments (difference between chlorophyll ‘a’&‘b’, carotenoids and xanthophyll), photochemical phase - pigment systems, cyclic and non-cyclic photophosphorylation, chemiosmotic hypothesis; biosynthetic phase - C3 cycle – graphic representation in correct sequence (carboxylation, glycolytic reversal and regeneration of pentose); Kranz anatomy, graphic representation of C4 cycle (Hatch and Slack pathway); Differences between C3 and C4 plants, C3 and C4 cycles, Photosystems I and II, Photorespiration pathway in brief; significance of photorespiration; explanation
of how RuBP carboxylase acts as RuBP oxygenase. Blackman’s Law of limiting factors, factors affecting photosynthesis (light, CO2, temperature, and water).
(ii) Respiration in Plants
Exchange of gases; cellular respiration - glycolysis, fermentation (anaerobic), TCA
cycle and electron transport system (aerobic); energy relations - number of ATP
molecules generated; amphibolic pathways; respiratory quotient.
Types of respiration; mechanism of respiration: glycolysis, Krebs’ cycle, ETS (only flowchart). Oxidative phosphorylation – definition; Brief idea of fermentation and Amphibolic pathway. Definition of respiratory quotient and RQ values of carbohydrates, proteins and fats.
(iii) Plant Growth and Development
Seed germination; phases of plant growth; plant growth rate; differentiation, dedifferentiation and redifferentiation; sequence of developmental processes in a plant cell; growth regulators - auxin, gibberellin, cytokinin, ethylene, ABA.
Definition of hypogeal, epigeal and viviparous germination with two examples of each. A brief idea about differentiation, dedifferentiation and redifferentiation. Phases of growth in meristems, growth rate – definition; measurement of growth by direct method and use of auxanometer, factors affecting growth.
Discovery and physiological role of growth regulators in plants (such as auxins, gibberellins, cytokinins, ethylene and abscisic acid – four effects of each); application of growth regulators.
5. Human Physiology
(i) Breathing and exchange of gases.
Respiratory organs in animals (recall only); Respiratory system in humans; mechanism
of breathing - exchange of gases, transport of gases and regulation of breathing,
respiratory volumes; disorders related to respiration.
Organs involved in respiration; mechanism of pulmonary gas exchange; breathing process should be explained showing the action of diaphragm and intercostal muscles, regulation of breathing ; transport of oxygen in the blood, oxyhaemoglobin dissociation curve; transport of CO2; chloride shift, pulmonary air volumes and lung capacities; disorders of respiratory system such as - asthma, emphysema, occupational respiratory disorders.
(ii) Body fluids and circulation.
Composition of blood, blood groups, coagulation of blood; composition of lymph and its functions; human circulatory system - structure of human heart and blood vessels; cardiac cycle, cardiac output, ECG; double circulation; regulation of cardiac activity; disorders of circulatory system.
Composition of blood plasma, functions of plasma proteins, blood corpuscles. Importance of ABO groups in blood transfusion, Rh factor and its importance in transfusion and pregnancy; clotting of blood to be taught briefly; lymphatic system – a brief idea of lymph (composition and function), Difference between closed and open vascular system; external and internal structure of heart; working of the heart and blood flow through the heart during different phases should be described under the following headings - auricular systole, auricular
diastole, ventricular systole, ventricular diastole and joint diastole; definition of stroke
volume and cardiac output, regulation of heart beat, ECG; arterial blood pressure
(systolic and diastolic), double circulation.
The internal structure of artery, vein and capillary. Importance of ABO groups in blood transfusion, Rh factor and its importance in transfusion and pregnancy; clotting of blood to be taught briefly; lymphatic system – a brief idea of lymph (composition and function),
lymphatic capillaries and lymph nodes; disorders of the circulatory system such as
hypertension, coronary artery disease, angina pectoris and heart failure.
(iii)Excretory products and their elimination.
Modes of excretion - ammonotelism, ureotelism, uricotelism; human excretory system - structure and function; urine formation, osmoregulation; regulation of kidney function, renin - angiotensin, atrial natriuretic factor, ADH; role of erythropoietin; role of other organs in
excretion; disorders of the excretory system - uraemia, renal failure, renal calculi,
nephritis; dialysis and artificial kidney, kidney transplant.
Define, differentiate and explain the terms ammonotelism, ureotelism and uricotelism;
external and internal structure of the kidney (L.S.); structure of nephron; physiology of
urine formation - ultra filtration, selective reabsorption and active (tubular) secretion.
Counter current system, regulation of urine formation, definition and regulation of
micturition, renin-angiotensin-aldosterone system, role of atrial natriuretic factor, ADH
and erythropoietin.
Role of skin, liver and lungs in excretion.
Homeostasis – definition. Disorders of the excretory system - uraemia, renal failure, renal calculi, nephritis.
Haemodialysis; Kidney transplant.
(iv) Locomotion and Movement
Types of movement - ciliary, flagellar, muscular; skeletal muscles - contractile proteins and muscle contraction; skeletal system and its functions; joints; disorders of muscular and skeletal system.
Locomotion: Basic aspects of human skeleton (number and names of the bones of axial and appendicular skeleton).
Functions of human skeleton; different types of joints - their location and function; general properties of muscles; structure of skeletal muscle - sliding filament theory of muscle contraction; chemical events during muscle contraction; definition of summation, tetanus, rigor mortis, differences between red and white muscles.
Disorders of muscular and skeletal system: (i) Myasthenia gravis, (ii) Tetany, (iii) Muscular dystrophy, (iv) Arthritis, (v) Osteoporosis, (vi) gout.
(v) Neural Control and Coordination
Neuron and nerves; nervous system in humans - central nervous system; peripheral nervous system and visceral nervous system; generation and conduction of nerve impulse.
Structure and functions of various parts of the brain and spinal cord; conduction of nerve impulses through nerve fibre (nonmyelinated and myelinated) and through synapse.
(vi) Chemical Co-ordination and Integration
Endocrine glands and hormones; human endocrine system - hypothalamus, pituitary, pineal, thymus, thyroid, parathyroid, adrenal, GI tract, pancreas, gonads; mechanism of hormone action (elementary idea); role of hormones as messengers and regulators, hypo - and hyperactivity and relate d disorders; dwarfism, acromegaly, cretinism, goiter, exophthalmic goiter, diabetes mellitus and diabetes insipidus, Grave’s disease, Addison's disease.
Brief idea of location of endocrine glands; role of hypothalamus; hormones secreted by different lobes of pituitary and their functions; feedback control of tropic hormones to be discussed giving examples; hormones of pineal, thymus, thyroid, parathyroid, pancreas, adrenal glands, GI tract (gastrin, secretin, GIP, CCK-PZ) and gonads; mechanism of hormone action (through cAMP and steroid hormones only); effects of hypo secretion and hyper secretion of various hormones of the above mentioned glands.
Note: Diseases related to all the human physiological systems to be taught in brief
Internal Assessment
Project Work And Practical File
15 Marks
Project Work – 10 Marks
Candidate is to creatively execute one project/assignment on any aspect of Biology. Preference is to be given to investigatory projects. Following is only a suggestive list of projects. Teachers may assign or students may choose any one project of their choice.
(i) Project related to experiment on any aspect of plant life/animal life.
(ii) Project related to any aspect of environment.
(iii) Diabetes.
(iv) Endocrine disorders.
(v) Yeast fermentation and production of alcohol or any other commercial industry dependant on plants and/or animals or their products.
In addition, students may be taught how to culture:
− Earthworms.
− Protozoans.
− Moulds.
− Setting up of an aquarium.
Suggested Evaluation Criteria for Project Work:
Format of the Project:
| – Content |
| – Introduction |
| – Presentation (graphs, tables, charts, newspaper cuttings, diagrams, photographs, statistical analysis if relevant) |
| – Conclusion/ Summary |
| – Bibliography |
Practical File – 5 Marks
Each practical done during the year, needs to be recorded by the student in the Practical file and the same must be checked, signed and dated by the teacher.
Teachers are required to assess students on the basis of the Biology Practical file maintained by them during the academic year.
