Students studying Biology in Class 11 under the Council for the Indian School Certificate Examinations (CISCE) study different topics related to plants, animals, cells and the human body. The syllabus helps students understand how living organisms function, how they grow and how different biological processes take place.
According to the official CISCE syllabus for the ISC Examination Year 2027, Class 11 Biology is divided into five major units. These units cover basic biological concepts and introduce students to important topics that are useful for higher studies in science.
The subject includes both theoretical and practical learning. Students not only study concepts from textbooks but also perform experiments and complete project work to understand Biology better.
Also read: ISC Class 11 Subject-Wise Syllabus 2026-27: Download Free PDF for Board Exam
ICSE Class 11 Biology Syllabus 2026-27: Complete Unit-Wise Topics
The Biology syllabus has five units. Each unit covers a different area of life science, from the classification of living organisms to the working of the human body.
The following table shows all five units and their marks weightage in the theory examination.
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| Unit Number | Biology Units | Marks Allotted |
|---|---|---|
| 1 | Diversity of Living Organisms | 9 |
| 2 | Structural Organisation in Animals and Plants | 11 |
| 3 | Cell: Structure and Function | 15 |
| 4 | Plant Physiology | 17 |
| 5 | Human Physiology | 18 |
| Total | 70 |
1. Diversity of Living Organisms – 9 Marks
This unit introduces students to the different types of living organisms and how scientists classify them. Students learn why classification is important and how plants, animals and microorganisms are grouped.
The main topics include:
| Core Sub-Topic | Important Covered Topics |
|---|---|
| Taxonomy & Systematics | The Living World, taxonomy and systematics Scientific naming of organisms and the importance of classification |
| Systematics & Microbial Diversity | Five-kingdom classification and three domains of life Characteristics of bacteria, fungi, viruses and other microorganisms |
| Plant & Animal Kingdoms | Plant Kingdom, including algae, bryophytes, pteridophytes and gymnosperms Animal Kingdom, including non-chordates and chordates |
Students also learn about the basic features of different groups of plants and animals, along with suitable examples.
2. Structural Organisation in Animals and Plants – 11 Marks
This unit explains how different parts of plants and animals are arranged and how they perform specific functions.
Key areas of study include:
| Core Sub-Topic | Important Covered Topics |
|---|---|
| Plant Morphology | Morphology of flowering plants Structure and modifications of roots, stems, and leaves Structure of flowers and types of inflorescence |
| Plant Anatomy & Tissues | Different types of plant tissues and their functions Internal structure of roots, stems, and leaves |
| Animal Morphology & Anatomy | Morphology and anatomy of frogs, including their major body systems |
Students learn how plant parts are designed for different purposes, such as storing food, providing support and absorbing water. They also study the basic structure and working of different systems in frogs.
3. Cell: Structure and Function – 15 Marks
Cells are the basic building blocks of all living organisms. This unit helps students understand how cells are formed, how they work and why they are important for life.
The main topics include:
| Core Sub-Topic | Important Covered Topics |
|---|---|
| Cell Structure & Organelles | Cell theory and the basic structure of cells Differences between plant and animal cells Cell organelles such as mitochondria, ribosomes, plastids and the nucleus |
| Biomolecules & Enzymes | Biomolecules, including carbohydrates, proteins, fats and enzymes |
| Cell Division & Reproduction | Cell cycle and cell division Mitosis and meiosis, along with their stages and importance |
Students also study how different cell parts perform specific functions and how cells divide to support growth and reproduction.
4. Plant Physiology – 17 Marks
This unit focuses on the different activities that take place inside plants. It explains how plants prepare food, release energy and grow.
Primary topics covered are:
| Core Sub-Topic | Important Covered Topics |
|---|---|
| Photosynthesis | Photosynthesis in higher plants Light and dark reactions of photosynthesis C3 and C4 pathways |
| Respiration | Respiration in plantsGlycolysis, Krebs cycle, and electron transport system |
| Plant Growth & Regulators | Plant growth and development Seed germination and different stages of plant growth Plant growth regulators such as auxins, gibberellins, cytokinins, ethylene, and abscisic acid |
Students understand how plants make their own food using sunlight, how they obtain energy and how different hormones control their growth.
5. Human Physiology – 18 Marks
Human Physiology is the highest-weightage unit in the Class 11 Biology theory paper. It explains how different organs and systems work together to keep the human body healthy and functioning.
The main topics include:
| Core Physiological System | Important Covered Topics |
|---|---|
| Respiration & Circulation | Breathing and exchange of gases Body fluids and circulation |
| Excretory & Locomotor Systems | Excretory products and their elimination Locomotion and movement |
| Control, Coordination & Integration | Neural control and coordination Chemical coordination and integration |
Students study the structure and functions of important organs such as the heart, lungs, kidneys and brain. They also learn about blood circulation, urine formation, muscle movement, hormones and the nervous system.
ICSE Class 11 Biology Exam Pattern 2026-27
The Biology examination includes theory, practical examinations, project work and a practical file. The total assessment is 100 marks.
| Assessment Component | Marks Allotted | Duration |
|---|---|---|
| Theory Paper (Paper I) | 70 | 3 hours |
| Practical Paper (Paper II) | 15 | 3 hours |
| Project Work | 10 | — |
| Practical File | 5 | — |
| Total | 100 |
The theory paper tests students' understanding of biological concepts, while the practical examination checks their ability to perform experiments, use laboratory equipment and identify different biological specimens.
Practical Topics in Class 11 Biology
Practical learning is an important part of the Biology syllabus. Students are expected to perform experiments, prepare slides, observe specimens and record their findings.
Some important practical topics mentioned in the official syllabus are:
| Practical Category | Experimental Activities / What Students Have to Do |
|---|---|
| Microscopy & Cell Biology | Learn the usage of dissecting and compound microscopes.Prepare temporary slides of onion peel to observe plant cell structures. Study and identify the different stages of mitosis using onion root tips. |
| Biochemical Analysis | Test various food samples to detect the presence of starch, glucose, sucrose, proteins, and fats.Study the disruptive effects of heat and alcohol on beetroot cell membranes. |
| Plant Physiology | Separate different plant pigments using paper chromatography. Study the phenomena of osmosis and plasmolysis in plant tissues. |
| Spotting & Identification | Identify, classify, and draw virtual or preserved plant and animal specimens. |
Students must also maintain a practical file containing records of the experiments performed during the academic year.
Which Units Carry the Highest Marks in ISC Class 11 Biology?
According to the official marks distribution, Human Physiology carries the highest weightage of 18 marks, followed by Plant Physiology with 17 marks. Cell: Structure and Function carries 15 marks.
Students should pay attention to all five units instead of preparing only the high-weightage chapters. They should also practise labelled diagrams, understand important biological terms and revise practical experiments regularly.
Where to Download the ISC Class 11 Biology Syllabus PDF?
Students can check and download the complete Biology syllabus directly from the official CISCE website.
- Official syllabus PDF: Download ISC Biology Syllabus 2027
The document contains detailed chapter-wise topics for Class 11, practical requirements, project work guidelines and marks distribution.
Important clarification: Class 11 under CISCE is officially part of the ISC curriculum, whereas ICSE refers to the Class 10 examination. Therefore, students looking for the Class 11 Biology syllabus should refer to the ISC Biology syllabus.
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