CBSE Class 12 Biology Syllabus 2026 Overview - Unit Wise Weightage, Exam Pattern & Important Tips

CBSE Class 12 Biology syllabus for the 2025–26 academic year is aimed at enhancing conceptual understanding of the subject in the major biological areas and also helps students for the board examination and medical entrance exams. The theory paper is held for three hours and is worth a total of 70 marks.

CBSE Exam Pattern: Class 12 Biology

Practical Exam:

Theoretical Exam:

Syllabus Divided into Five Units: Weightage Details

• Reproduction (16 Marks)

This unit focuses on the reproduction of living organisms and the continuity of life. It contains topics on human reproduction, reproductive health, reproduction in flowering plants and the biology behind. Questions on this unit are generally predictable and concept-based, and hence, it is one of the most important sections in the syllabus.

• Genetics and Evolution (20 Marks)

This is a high-weightage unit constituting maximum marks for the paper. Topics on inheritance patterns, genetic disorders, molecular genetics, and evolution are covered in this unit. It is the fundamental chapters that are required for understanding several advanced topics and preparing long-answer questions frequently.

• Biology and Human Welfare (12 Marks)

This unit is relevant to our daily life in explaining human health and diseases, immunity and the welfare function of microbes. One can easily attempt these questions as it is mainly application-based.

• Biotechnology and Its Applications (12 Marks)

This unit is about latest Genetic Engineering (Recombinant DNA Technology), biotechnological processes and their applications. One may score well on this unit with proper attempt, diagrammatic explanations and stepwise understanding.

• Ecology and Environment (10 Marks)

This unit deal with several ecological concepts, including ecosystems, biodiversity, environmental issues and conservation. The unit is short and is a good unit to revise in the last days of the year. Most of the questions are of a short-answer/case-based type.

⬇ Download CBSE Class 12 Biology Syllabus 2026

CBSE Class 12 Exam Related Resources and Study Material

Tips for Effective Preparation for CBSE Class 12 Biology Exam

To score well in your Class 12 Biology exam, follow these expert tips to make your preparation more effective:

1. Master the NCERT Textbook

The NCERT Biology textbook is your best companion for Class 12 Biology preparation. Most questions in the exam are directly based on NCERT concepts, so ensure that you understand all the chapters thoroughly.

2. Focus on Diagrams and Labeling

Biology is a subject that requires you to understand and draw diagrams effectively. Practice drawing labeled diagrams for all important topics like the structure of a cell, human reproductive system, and types of tissues.

3. Make Short Notes

While studying, make concise notes of key concepts, important points, and definitions. This will help you during revision and in last-minute preparations.

4. Solve Previous Year Question Papers

Solve as many previous year question papers as possible to understand the exam pattern, marking scheme, and types of questions asked. This will also help you manage time effectively during the exam.

5. Practice Writing Detailed Answers

For long-answer questions (5 marks), practice writing detailed and structured answers. Make sure to include all relevant points, use proper terminology, and format your answers clearly.

Students Can Also Check: CBSE Class 12 Study Resources

Importance of CBSE Class 12 Biology for Boards & NEET

The syllabus of the CBSE 12th Biology exam provides the base for the medical entrances, as approximately the syllabus of the NEET Biology exam is based on the NCERT 11th and 12th class concepts. Clear concepts on the 12th Biology exam help students fetch higher marks in the CBSE board exam, along with better knowledge to solve NEET MCQs correctly and efficiently. Our teachers prepare students in Biology by prioritising conceptual understanding and NCERT-based learning, helping them excel in CBSE board exams as well as medical entrance tests like NEET.

You Can Also Check NEET-related information, including exam details, latest updates, and eligibility criteria as given below :

CBSE Class 12 Biology Syllabus 2025, Check Exam Pattern

Biology is one of the most fascinating subjects in the CBSE Class 12 curriculum. Whether you are aiming for a career in medicine, research, or any other field related to life sciences, understanding the CBSE Class 12 Biology Syllabus 2025 is crucial. In this guide, we’ll walk you through the latest syllabus, explain the important topics, provide tips for efficient preparation, and help you understand the exam pattern.

CBSE Class 12 Biology Syllabus 2025 Overview

The CBSE Class 12 Biology syllabus is designed to develop a student’s understanding of the biological world. It focuses on complex biological processes and systems, offering detailed insights into topics like genetics, biotechnology, ecology, human physiology, and plant biology. The syllabus emphasizes both theoretical knowledge and practical skills.

The subject is divided into two sections: Theory and Practical. The total marks for the theory exam are 70, while the practical exam carries 30 marks.

CBSE Class 12 Biology Highlights:

• Subject Name: Biology
• Total Marks for Theory: 70
• Total Marks for Practical: 30
• Duration of Exam: 3 hours
• Total Marks: 100
• Internal Assessment: 30 (for practicals)

CBSE Class 12 Biology Unit-Wise Breakdown 2025

The Class 12 Biology syllabus is divided into various units, each focusing on specific biological concepts. Below is a detailed unit-wise breakdown:

CBSE Class 12 Biology Syllabus 2025 (Detailed)

1. Reproduction (14 Marks)

This unit focuses on the biological processes involved in the reproduction of both plants and animals. Understanding the intricacies of reproduction is essential for higher studies in biology.

• Reproduction in Organisms:

  • Asexual and sexual reproduction
  • Reproductive cycles in plants and animals
  • Flower structure, pollination, fertilization, and seed formation

• Human Reproduction:

  • Male and female reproductive systems
  • Reproductive health and contraception
  • Menstrual cycle and hormonal regulation

• Reproductive Health:

  • Infertility, assisted reproductive technologies (ART), and in-vitro fertilization (IVF)

2. Genetics and Evolution (18 Marks)

This is one of the most critical sections in the Class 12 Biology syllabus. Genetics explains heredity and variation, while evolution introduces how life forms evolve over time.

• Mendelian Genetics:

  • Laws of inheritance and variations
  • Monohybrid and dihybrid crosses
  • Gene interactions and genetic disorders

• Molecular Genetics:

  • Structure and function of DNA and RNA
  • Transcription, translation, and genetic code
  • DNA replication and repair mechanisms

• Evolution:

  • Darwin’s theory of evolution
  • Natural selection and genetic drift
  • Speciation and evidence of evolution

3. Biology and Human Welfare (12 Marks)

This unit explores the connection between biology and its impact on human welfare. It includes a study of diseases, health, and agriculture.

• Human Health and Diseases:

  • Types of diseases (infectious and non-infectious)
  • Immunity and vaccines
  • Major human diseases like tuberculosis, cancer, and malaria

• Improvement in Food Production:

  • Plant breeding, hybridization, and genetic modification
  • Animal husbandry and fish farming

• Biological Products:

  • Biofertilizers, biopesticides, and their applications in agriculture

4. Biotechnology and Its Applications (10 Marks)

This section covers the rapidly growing field of biotechnology and its applications in medicine, agriculture, and industry.

• Principles of Biotechnology:

  • Techniques like genetic engineering and recombinant DNA technology
  • Gene cloning and gene therapy

• Applications of Biotechnology:

  • Production of insulin, human growth hormone, and vaccines
  • Genetic modification of plants and animals for better yield and disease resistance

5. Ecology and Environment (16 Marks)

This unit covers ecological principles, environmental issues, and conservation strategies, making it a highly relevant topic for students interested in sustainability and environmental science.

• Organisms and Populations:

  • Habitat, niche, and interactions
  • Population growth models and factors regulating population size

• Ecosystems:

  • Energy flow, food chains, and food webs
  • Biogeochemical cycles: carbon, nitrogen, and water cycles

• Biodiversity and Conservation:

  • Biodiversity hotspots, extinction, and conservation strategies
  • Environmental pollution, global warming, and their impact

CBSE Class 12 Biology Exam Pattern 2025

The CBSE Class 12 Biology exam pattern is divided into two main sections: the theory paper and the practical exam. Here's how the paper is structured:

Theory Exam (70 Marks)

Practical Exam (30 Marks)

The CBSE Class 12 Biology Syllabus 2025 is vast and comprehensive, but with structured preparation, you can excel in it. Stay consistent with your studies, focus on key topics, practice regularly, and utilize all available resources, including NCERT textbooks and previous years' papers. With the right approach, you will be well-equipped to ace your Biology exam and lay the foundation for your future academic endeavors. Good luck with your preparations!

CBSE Class 12 Biology Syllabus 2026 FAQs

Q1. Is the Class 12 Biology syllabus expected to change in 2026?

Answer: The syllabus for Class 12 Biology typically remains consistent with minor adjustments. It is always a good idea to check the official CBSE website for updates.

Q2. How can I score full marks in the Biology exam?

Answer: To score full marks, you must master the core concepts, practice diagrams, and solve previous years' question papers. Pay attention to details, and make sure your answers are structured and comprehensive.

Q3. Are practicals important for the final score?

Answer: Yes, practical exams carry 30 marks, and performing well in practicals can significantly improve your overall score. Be thorough with the practicals mentioned in your syllabus and ensure you maintain a neat record.

Q4. How can I improve my understanding of genetics and evolution?

Answer: Genetics and evolution can be complex, but breaking down the topics and understanding fundamental concepts like Mendel's laws, DNA structure, and evolutionary processes will make these topics easier to grasp. Regular practice and solving related problems will also help.