ISC Class 12 Biology Weightage 2025 Chapter-Wise Marks Distribution

ISC Class 12 Biology Weightage 2025: The Council for the Indian School Certificate Examinations (CISCE) has released the unit and chapter-wise marks distribution for the ISC Class 12 Biology exam for the 2025-2026 academic session.

ISC Class 12 Preparation Tips 2024

ISC Class 12 Biology Weightage 2025 Chapter-Wise Marks Distribution

ISC Class 12 Chemistry Weightage 2025

Unit 1: Reproduction

• Key Insights : The unit on reproduction is the most extensive, contributing 16 marks without options, and 23 marks with options. The chapter on Sexual Reproduction in Flowering Plants is crucial, covering topics like pollination, fertilization, and the structure of flowers. The chapters on Human Reproduction and Reproductive Health focus on human reproductive organs, their functions, and common health issues related to reproduction.

Unit 2: Genetics and Evolution

• Key Insights : The study of inheritance patterns, genetic disorders, and the molecular basis of inheritance (DNA structure, RNA, protein synthesis) forms the core of this unit. The Evolution chapter helps in understanding how species evolve over time, contributing 6 marks to the exam.

Unit 3: Biology and Human Welfare

• Key Insights : Human Health and Diseases is a major chapter, worth 8 marks without options. It covers a range of topics, including infectious diseases, their prevention, and non-communicable diseases. Microbes in Human Welfare discusses the beneficial role of microbes in processes like fermentation, waste treatment, and antibiotic production.

Unit 4: Biotechnology and its Applications

• Key Insights : Topics like Principles of Biotechnology and Applications of Biotechnology are essential for understanding genetic engineering, recombinant DNA technology, and their use in medicine and agriculture.

Unit 5: Ecology and Environment

• Key Insights : The topics under Ecology and Environment , including Ecosystems , Biodiversity , and Conservation , help students understand the functioning of ecosystems, the role of biodiversity, and the need for environmental protection.

ISC Class 12 Biology Practical Work Evaluation Criteria

Project Work (10 Marks) :

• Content : Clear and detailed explanation of the chosen topic.
• Introduction : Well-researched introduction to the project.
• Presentation : Use of graphs, tables, charts, photographs, and relevant diagrams for clarity.
• Conclusion/Summary : A well-drawn conclusion summarizing the findings.
• Bibliography : Proper citations for sources used.

Practical File (5 Marks) :

• Every experiment must be recorded.
• Experiments should be checked, signed, and dated by the subject teacher.
• A neatly organized file that clearly documents the practicals performed throughout the academic year.

Study Tips for ISC Class 12 Biology 2025

1. Prioritize High-Weightage Units : Focus more on the high-weightage chapters such as Reproduction , Genetics , and Human Health . These units contribute a significant portion of the marks in the exam.
2. Conceptual Clarity : Biology is all about understanding concepts in depth. Ensure that you have a clear understanding of the basic principles of each chapter, especially the molecular and cellular processes.
3. Revise Regularly : Consistent revision will help reinforce concepts. Create summary notes for each chapter to make revision easier.
4. Focus on Practical Work : Keep your practical file up to date and ensure you practice all experiments thoroughly. Make sure your project is well-researched, and you present it creatively.
5. Use Visual Aids : Diagrams, flowcharts, and tables are essential for explaining biological processes. Make sure to practice drawing and labeling them accurately.
6. Solve Previous Years’ Papers : Practice solving ISC Biology papers from previous years to familiarize yourself with the pattern and the types of questions asked.
7. Stay Updated on Environmental Issues : As Ecology and Environment topics are becoming more relevant, stay updated with current environmental issues and case studies, which might help in answering questions with a modern context.