Biology (Theory) ISC (Science) ISC Class 11 CISCE Syllabus 2025-26

• 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

• 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

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

• Amitosis (Direct Cell Division)
• Mitosis
• Closed and Open Mitosis
• Cytokinesis
• Significance of Mitosis
• Meiosis

• Meiosis I-Reduction Division

• Significance of Meiosis

• Passive Transport

• Characteristics of diffusion
• Significance of diffusion in Plants

1. Channel Protein
2. Carrier Protein

• Active Transport

• Water Potential (ψ)
• Factors affecting water absorption

• Opening and Closing of Stoma

• Sources of minerals
• Classification of minerals on the basis of their quality requirement:

1. Essential minerals 
2. Non-essential minerals 

• Classification of minerals on the Basis of their quantity requirement:

1. Microelement minerals
2. Macroelement minerals

• Symptoms of Mineral deficiency in plants
• Toxicity of Micronutrients
• Minerals salt absorption: Passive Absorption and Donnan equilibrium

• Priestley's experiment

• 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

• Blackman - Law of limiting factors
• Factors affecting photosynthesis

1. External Factors:
   1) Availability of sunlight
   2) Temperature
   3) Water
   4) Humidity
   5) CO₂ Concentration [atmospheric]
   6) O₂ availability
2. Internal Factors:
   1) Number of leaves
   2) Size of leaves
   3) Leaf age
   4) Orientation of leaves
   5) Mesophyll cells and chloroplasts
   6) Internal CO₂ concentration
   7) Anatomy of leaf

• 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

• Glycolysis
• Glycolysis Pathway

• Cellular respiration
• Types of cellular respiration

1. Aerobic Respiration
2. Anaerobic Respiration

• Aerobic respiration in plant/animal
• Anaerobic respiration in plant/animal
• Differences in anaerobic respiration in plants and animals

• TCA Cycle (Tricarboxylic Acid Cycle)
• Steps of TCA 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

• Phases of Plant Growth

1. Phase of cell division/ formation (Meristematic Phase)
2. Phase of cell enlargement/ elongation (Elongation Phase)
3. Phase of Cell maturation/ differentiation (Maturation Phase)

• Photoperiodism

1. Short Day Plants (SDP)
2. Long Day Plants (LDP)
3. Day Neutral Plants (DNP)

• Phytochrome

• Sequence of Developmental Processes in a Plant Cell

• Process of Seed and Fruit Development  
• Significance of seed and fruit formation
• Dormancy

• 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

• 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

Disorders of the respiratory system

• Emphysema
• Chronic bronchitis
• Acute bronchitis
• Sinusitis
• Laryngitis
• Pneumonia
• Asthma
• Occupational Respiratory Disorderssilicosis, asbestosis

• Neural control
  1) Respiratory rhythm centre
  2) Pneumotaxic centre
• Chemical Control
  1) Chemosensitive Area
  2) Chemoreceptors

• Clotting of Blood (Coagulation)
• Blood clotting in a test tube

• Human Blood Groups
• Rh Factor
• Blood Donation
• Blood Banks
• Blood Donor
• Blood Recipient

• Lymph and Lymphatic System
• Composition of Lymph
• Functions of Lymph

• Types of Closed Circulation:

1. Single circulation
2. Double circulation
   - Systemic circulation
   - Pulmonary circulation
   - Coronary circulation

• Hepatic Portal System

• 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

• Modes of Excretion

1. Ammonotelism
2. Ureotelism 
3. Uricotelism 

• Nephridiopores
• Types of nephridia

1. Protonephridia
2. Metanephridia

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

• Ultrafiltration
• Reabsorption
• Tubular secretion (Renal Secretion)
• Distal convoluted tubule (DCT)
• Collecting duct

• Osmoregulation
• Regulation of Kidney Function

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

• Excretory role of skin
• Excretory role of lungs
• Excretory role of liver

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

• Dialysis
• 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

• Reflexes
• Types of actions

1. Voluntary actions 
2. Involuntary actions

• Sense Organs (Receptors)
• Olfactory receptors
• Gustatory receptors
• Classification of Receptors
  (i) Thermoreceptors
  (ii) Tactile receptors / Tangoreceptors
  (iii) Chemoreceptors
  (iv) Phonoreceptors
  (v) Statoreceptors
  (vi) Photoreceptors
  (vii) Pain receptors / Nociceptors
  (viii) Proprioceptors

• Structure and Components
• Photoreceptors and Eye Muscles

• Structure of Human Ear
• Function of Human Ear

Human Endocrine System

• Properties of Hormones 
• Mechanism of hormone action 

• 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