Revised CBSE Syllabus 2021 for Class 11 Biology

Revised CBSE Syllabus 2021 for Class 11 Biology


CLASS XI (2020 -21) (THEORY)


Time:3 Hours                                                                                                    Max. Marks: 70



Unit Title Marks
I Diversity of Living Organisms 15
II Structural Organization in Plants and Animals 8
III Cell: Structure and Function 15
IV Plant Physiology 15
V Human Physiology 17
Total 70


Unit-I Diversity of Living Organisms


Chapter-1: The Living World

What is living? Biodiversity; Need for classification; three domains of life; concept of species and taxonomical hierarchy; binomial nomenclature.


Chapter-2: Biological Classification

Five kingdom classification; Salient features and classification of Monera, Protista and Fungi into major groups; Lichens, Viruses and Viroids.


Chapter-3: Plant Kingdom

Salient features and classification of plants into major groups – Algae, Bryophyta, Pteridophyta and Gymnospermae. (salient and distinguishing features and a few examples of each category).


Chapter-4: Animal Kingdom

Salient features and classification of animals, non-chordates up to phyla level and chordates up to class level (salient features and distinguishing features of a few examples of each category). (No live animals or specimen should be displayed.)


Unit-II Structural Organization in Animals and Plants


Chapter-5: Morphology of Flowering Plants

Morphology of inflorescence and flower, Description of 01 family: Solanaceae or Liliaceae (to be dealt along with the relevant experiments of the Practical Syllabus).


Chapter-7: Structural Organisation in Animals

Animal tissues.

Unit-III Cell: Structure and Function


Chapter-8: Cell-The Unit of Life

Cell theory and cell as the basic unit of life, structure of prokaryotic and eukaryotic cells; Plant cell and animal cell; cell envelope; cell membrane, cell wall; cell organelles – structure and function; endomembrane system, endoplasmic reticulum, golgi bodies, lysosomes, vacuoles, mitochondria, ribosomes, plastids, microbodies; cytoskeleton, cilia, flagella, centrioles (ultrastructure and function); nucleus.


Chapter-9: Biomolecules

Chemical constituents of living cells: biomolecules, structure and function of proteins, carbohydrates, lipids, nucleic acids; Enzymes- types, properties, enzyme action.


Chapter-10: Cell Cycle and Cell Division

Cell cycle, mitosis, meiosis and their significance



Unit-IV Plant Physiology


Chapter-13: Photosynthesis in Higher Plants


Photosynthesis as a means 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.


Chapter-14: 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.


Chapter-15: Plant – Growth and Development

Growth regulators – auxin, gibberellin, cytokinin, ethylene, ABA.


Unit-V Human Physiology


Chapter-17: Breathing and Exchange of Gases

Respiratory organs in animals (recall only); Respiratory system in humans; mechanism of breathing and its regulation in humans – exchange of gases, transport of gases and regulation of respiration, respiratory volume; disorders related to respiration – asthma, emphysema, occupational respiratory disorders.


Chapter-18: Body Fluids and Circulation

Composition of blood, blood groups, coagulation of blood; composition of lymph and its function; 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 – hypertension, coronary artery disease, angina pectoris, heart failure.


Chapter-19: 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 and diabetes insipidus; role of other organs in excretion; disorders – uremia, renal failure, renal calculi, nephritis; dialysis and artificial kidney, kidney transplant.


Chapter-20: Locomotion and Movement

Skeletal muscle, contractile proteins and muscle contraction.


Chapter-21: 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.


Chapter-22: Chemical Coordination and Integration

Endocrine glands and hormones; human endocrine system – hypothalamus, pituitary, pineal, thyroid, parathyroid, adrenal, pancreas, gonads; mechanism of hormone action (elementary idea); role of hormones as messengers and regulators, hypo – and hyperactivity and related disorders; dwarfism, acromegaly, cretinism, goiter, exophthalmic goiter, diabetes, Addison’s disease.

Note: Diseases related to all the human physiological systems to be taught in brief.




Time Allowed : Three hours                                                                             Max. Marks: 30



Evaluation Scheme Marks
One Major Experiment Part A (Experiment No- 1,3) 5
One Minor Experiment Part A (Experiment No- 4,5,6) 4
Slide Preparation Part A (Experiment No- 2) 5
Spotting Part B 7
Practical Record + Viva Voce Credit to the students’ work over the academic session may be given 4
Project Record + Viva Voce 5
Total 30


A: List of Experiments

  1. Study and describe a locally available common flowering plant, from any one family: Solanaceae or Liliaceae (Poaceae, Asteraceae or Brassicaceae can be substituted in case of particular geographical location) including dissection and display of floral whorls, anther and ovary to show number of chambers (floral formulae and floral diagrams).
  2. Study of distribution of stomata in the upper and lower surfaces of
  3. Separation of plant pigments through paper
  4. Study of the rate of respiration in flower buds/leaf tissue and germinating
  5. Test for presence of sugar in
  6. Test for presence of albumin in


B. Study/Observer of the following (spotting)

  1. Parts of a compound
  2. Specimens/slides/models and identification with reasons – Bacteria, Oscillatoria, Spirogyra, Rhizopus, mushroom, yeast, liverwort, moss, fern, pine, one monocotyledonous plant, one dicotyledonous plant and one
  3. Virtual specimens/slides/models and identifying features of – Amoeba, Hydra, liverfluke, Ascaris, leech, earthworm, prawn, silkworm, honeybee, snail, starfish, shark, rohu, frog, lizard, pigeon and
  4. Tissues and diversity in shape and size of animal cells (squamous epithelium, smooth, skeletal and cardiac muscle fibers and mammalian blood smear) through temporary/permanent
  5. Mitosis in onion root tip cells and animal cells (grasshopper) from permanent


Practical Examination for Visually Impaired Students Class XI


Note: The ‘Evaluation schemes’ and ‘General Guidelines’ for visually impaired students as given for Class XII may be followed.


A.    Items for Identification/Familiarity with the apparatus / equipments/animal and plant material / chemicals etc. for assessment in practicals (All experiments)

  • Plants of Solanaceae – Brinjal, Petunia, any other or Liliaceae- Any of the
  • Mushroom, Succulents such as Aloe vera/Kalanchoe, Raisins,
  • Honey comb, Mollusc shell, Model of cockroach, Pigeon and Star


  • Compound microscope, Test tube, Petri dish, Beaker,
  • Chromatography paper, Chromatography chamber,


B.     List of Practicals

  1. Study one locally available common flowering plant of the family– Solanaceae or Liliaceae and identify inflorescence/flower.
  2. Study the parts of a compound microscope- eye piece and objective lens, mirror, stage, coarse and fine adjustment
  3. Study honey-bee/butterfly, snail shell, Starfish, Pigeon (through models).
  4. Identify the given specimen of a fungus – Mushroom, gymnosperm- pine cone

Note: The above practicals may be carried out in an experiential manner rather than recording observations.


Prescribed Books:

  1. Biology Class-XI, Published by NCERT
  2. Other related books and manuals brought out by NCERT (including multimedia)