Biology (Theory) ISC (Science) ISC Class 11 CISCE Syllabus 2026-27

• What is ‘Living’?
• Characteristics of living organisms

1. Growth
2. Reproduction
3. Cellular structure
4. Response to stimuli (Consciousness)
5. Homeostasis
6. Metabolism

• Difference  between anabolism and catabolism

• Diversity in the Living World
• Biodiversity
• Types of Biodiversity

1. Genetic Biodiversity
2. Species Biodiversity
3. Ecological Biodiversity

• Three Domains of life

• Domain Archaea
• Domain Bacteria
• Domain Eukarya (Eukaryotes)

• Taxonomical Aids
• Usage of Taxonomical Aids

1. Herbarium
2. Botanical Gardens
3. Biological museums
4. Zoological Parks
5. Key
6. Molecular taxonomy
7. Automated species identification tools

• Introduction
• Hierarchy Classification
• Five Kingdom Classification

• Introduction
• Experiment

• Kingdom Animalia
• Characteristics of Kingdom Animalia

• natural classification systems, phylogenetic classification systems

• characteristics (morphology, common name, major pigments, stored food, composition of cell wall, flagellar number and position of insertion, habitat, mode of sexual reproduction – isogamous, anisogamous and oogamous) and examples of Chlorophyceae, Phaeophyceae, Rhodophyceae; Economic importance of algae
• zoospores, isogamous, anisogamous, oogamous, algin, carrageen,The algae are divided into three main classes: Chlorophyceae, Phaeophyceae and Rhodophyceae
• Chlorophyceae - green algae
• Phaeophyceae - brown algae
• Rhodophyceae - red algae

• Bryophyta
• Activity

• Angiosperms
• Activity
• Classification of Angiosperms

• Kingdom Animalia
• Characteristics of Kingdom Animalia

Animal construction :- body plan (cell aggregate plan, blind-sac plan and tube-within-tube plan), symmetry (spherical, radial and bilateral symmetry), coelom development (diploblastic and triploblastic organisation in animals, acoelomate, pseudocoelomate, coelomate and haemocoelomate), segmentation

• Types of Root
• Experiment 1
• Experiment 2
• Experiment 3

features (nodes internodes, buds)

• The steam
• Characteristic features of the stem
• Functions of the stem
  (i) Primary functions
  (ii) Secondary functions
• Buds
• Types of Stem - Excurrent, Decurrent, Caudex, and Culm
• Modification of Stem
  1) Aerial modification of stem
  2) Subaerial stem modifications
  3) Underground stem modifications
  4) Stem Branching

parts of a simple leaf, venation

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), 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]

• Introduction
• Types of Meristematic Tissue

(tight, adhering and gap junctions)

(to be taught with the help of diagrams)

• Cell theory and cell as the basic unit of life
• Exception to Cell Theory 
• Protoplasm Theory
• Cell sizes and shapes

• Key Points: Cell

• Introduction
• Experiment
• Definition: Chromatin Fibres
• Key Points: Nucleus

Structure and Function of Proteins

amino acids – (structure: glycine, alanine, serine)

amino acids as zwitter-ion

examples of acidic, basic, neutral, sulphur containing amino acids

essential and nonessential amino acids

levels of protein structure (primary, secondary, tertiary and quaternary)

functions of proteins

• Carbohydrates
• Classification of carbohydrates

classification, structure and functions of fats and oils

• Key Points: Cell Division

• Passive Transport

• Characteristics of diffusion
• Significance of diffusion in Plants

1. Channel Protein
2. Carrier Protein

• Active Transport

• Photophosphorylation

1. Non-cyclic photophosphorylation
2. Cyclic Photophosphorylation

• difference between chlorophyll ‘a’&‘b’, carotenoids and xanthophyll
• Pigments Involved in Photosynthesis (Elementary Idea)

C3 and C4 pathways

• Definition: Photolysis
• Definition: Photophosphorylation

• Do plants breathe?
• The process of respiration in plants
• Respiration in roots
• Respiration in stems
• Respiration in leaves
• Types of respiration

1. Aerobic Respiration
2. Anaerobic Respiration

• Definition: Glycolysis

• Definition: Aerobic Respiration
• Definition: Anaerobic Respiration
• Key Points: Cellular Respiration

• Definition: Tricarboxylic Acid Cycle (Citric Acid Cycle or Kreb’s Cycle)

• Fermentation
• Process of Fermentation
• Types of Fermentation

1. Lactic Acid Fermentation
2. Alcohol Fermentation
3. Acetic acid Fermentation
4. Butyric acid Fermentation

• Advantages of Fermentation

• Characteristics of Growth in plants:
  1) Indeterminate or continuous growth
  2) Localised growth

• Sequence of Developmental Processes in a Plant Cell

• Vernalisation
• Kinds of varieties
  1) Spring variety
  2) Winter variety

• Alimentary canal
• The human alimentary canal consists following parts:

1. Buccal (oral) cavity
   a) Mouth
   b) Teeth - thecodont, Diphyodont, enamel, Types of Teeth: Incisors, Canines, Premolars, Molars, Dental Formula → Arrangement of teeth in each half of the upper and lower jaw
   c) Tongue
2. Pharynx
3. Oesophagus (food pipe)
4. Stomach: Cardiac region, Fundic region, Body (Main central region), Pyloric region.
5. Small Intestine: Duodenum, Jejunum, IIleum
6. Large Intestine: Caccum, Colon, Rectum, Anal canal
7. Anus: Wall of Alimentary canal
   i) Serosa
   ii) Muscularis
   iii) Submucosa
   iv) Mucosa

• In Buccal Cavity: Constituents of saliva, Salivary amylase, Lysozyme
• In Stomach:
  a) Gastric glands: Chief/ peptic (zymogen cells), Oxyntic/ parietal cells, Mucus neck cells, Gastric Juice, gastric secretion
• In Small Intestine: Intestinal juice (Succus entericus)
  a) Role of bite in fat digestion
  b) Role of Pancreatic Juice
  ⇒ In carbohydrate digestion
  ⇒ In protein digestion
  ⇒ In fat digestion
  ⇒ In Nucleic acid digestion
  c) Role of intestinal juice indigestion
  ⇒ In carbohydrate digestion
  ⇒ In protein digestion
  ⇒ In fat digestion
  ⇒ In Nucleic acid digestion
• Large Intestine
  ⇒ Neural and hormonal control on digestion process

• Absorption
• It is carried out by various processes:

1. Passive Absorption
   ⇒ Process
   a) Simple diffusion
   b) Osmosis
   c) Facilitated transport
2. Active absorption

• Absorption of fatty acids and glycerol
• Absorption in different parts of the alimentary canal
• Assimilation

• Disorders of the digestive system

1. Inflammation of the intestinal tract
2. Jaundice
3. Vomiting 
4. Diarrhoea
5. Constipation
6. Indigestion

• PEM (Protein-energy malnutrition)

1. Kwashiorkar
2. Marasmus

• Respiratory Organs in Animals
• gills, lungs

• Respiratory System
• Exchange of Gases in Lungs
• Significance of Respiration
• Key Points: Respiratory System

• Mechanism of Respiration
• Steps of Respiration

1. Tidal Volume (TV)
2. Inspiratory Reserve Volume (IRV)
3. Expiratory Reserve Volume (ERV)
4. Residual Volume (RV)
5. Inspiratory Capacity (IC)
6. Expiratory Capacity (EC)
7. Functional Residual Capacity (FRC)
8. Vital Capacity (VC)
9. Total Lung Capacity (TLC)

• Exchange of Gases - in Humans

• Definition: Closed Blood Circulatory System
• Definition: Open Blood Circulatory System
• Key Points: Fluids in Our Body

• Definition: Thrombokinase
• Definition: Clot
• Blood Platelets
• Function of Blood Platelets
• Key Points: Blood Platelets

• Definition: Blood Transfusion
• Definition: Blood Donor
• Definition: Blood Recipient
• Definition: Antigens
• Definition: Antibodies
• Definition: Universal Donor
• Definition: Universal Recipient
• Blood Groups
• Rh Factor
• Key Point: Blood Transfusion and Blood Groups

• Disorders of the Circulatory System:

1. Hypertension/ High blood pressure: Normal blood pressure
2. Coronary Artery Disease (CAD) or Atherosclerosis
3. Angina / Angina pectoris
4. Heart Failure: Myocardial infarction (Heart failure), Cardiac arrest, Heart attack, Stroke
5. Rheumatoid Heart Disease

• Introduction
• Human Excretory System Organs
• Excretion in Humans
• Mechanism of Excretion in Humans
• Dialysis

• Definition: Ultrafiltration
• Definition: Glomerular Filtrate
• Definition: Selective Absorption
• Definition: Tubular Secretion

• Definition: Osmoregulation
• Key Points: Osmoregulation

• Osmoregulation
• Regulation of Kidney Function

1. Renin-Angiotensin,
2. Atrial Natriuretic Factor (ANF)
3. ADH and Diabetes Inspidus

• Key Points: Excretory Organs

• Kidney stones
• Uremia
• Nephritis
• Renal Failure
• Diabetes
• Urinary tract infection
• Haemodialysis
• Peritoneal dialysis 
• Kidney transplant
• Renal Calculi
• Glomerulonephritis

• Dialysis
• Definition: Dialysis
• Definition: Artificial Kidney
• Types of Dialysis

• Movements
• Locomotion
• Locomotary movements
• Significance of locomotion

• Types of movement
  1) Amoeboid movement
  2) Ciliary movement
  3) Muscular movement

• Muscles
• Properties of muscles
• Classification of muscles

1. Based on their location
   (i) Skeletal muscles
   (ii) Visceral muscles
   (iii) Cardiac muscles
2. Based on their appearance
   (i) Striated muscles
   (ii) Smooth muscles
3. Based on nature
   (i) Voluntary muscles
   (ii) Involuntary muscles

• Skeletal System and Its Functions

• Disorders of Muscular and Skeletal System -

1. Myasthenia gravis
2. Tetany
3. Muscular dystrophy
4. Arthritis
5. Osteoporosis
6. Gout

• Definition: Reflex Action
• Key Points: Reflex Action

• Key Points: The Human Eye

• Key Points: Human Ear

• Definition: Endocrine System

• Mechanism of Hormone Action
• Hormones and their types
• Target cells have specific receptors

• Types of effects of hormones regulate metabolism and body functions
  1) Permissive effect
  2) Synergistic effect
  3) Antagonistic effect

• Gigantism
• Acromegaly
• Pituitary dwarfism
• Diabetes insipidus
• Graves' disease (Exophthalmic goiter)
• Cretinism
• Goitre
• Addison's disease
• Diabetes mellitus