ISC 12th Biology Marks Distribution 2026 Chapter-Wise

The ISC Class 12 Biology Marks Distribution 2026 shows how marks are given chapter-wise. It helps students understand which units carry more weight.

ISC 12th Biology Paper: The 2026 ISC Class 12 Biology marks distribution will provide the clear structure of marks for the theory portion i.e. ( 70 marks ) amongst various units and chapters. This pattern will give students an idea about the chapters (units Genetics, Evolution & Ecology, etc .) that have higher weightage in terms of marks. With this blueprint, students will be able to plan their revision in a better way by allocating more time to those sections that are high scoring and strengthening fundamental concepts that frequently appear in exams.

By knowing the chapter-wise weightage in advance, students can approach their preparation with better clarity and confidence. The distribution shows a good balance between theory, diagrams, application-based questions, and descriptive answers. It also helps in devising a focused study plan without missing a major unit while studying at home.

ISC Class 12 Biology Paper Unit-Wise Weightage Marks 2026

The table below highlights the ISC Class 12 Biology unit-weightage 2026 here:

Unit No.	Unit Name	Marks
I	Reproduction	14
II	Genetics & Evolution	20
III	Biology & Human Welfare	14
IV	Biotechnology	10
V	Ecology & Environment	12
Total		70

ISC Class 12 Biology 2026 – Chapter-Wise Detailed Blueprint

Below is the chapter-wise weightage based on the 2026 ISC Biology syllabus structure.

Unit	Chapter Name	Weightage (Approx.)
Unit I: Reproduction	Reproduction in Organisms	3
	Sexual Reproduction in Flowering Plants	4
	Human Reproduction	4
	Reproductive Health	3
Total		14 Marks
Unit II: Genetics & Evolution	Principles of Inheritance & Variation	7
	Molecular Basis of Inheritance	8
	Evolution	5
Total		20 Marks
Unit III: Biology & Human Welfare	Human Health & Diseases	5
	Strategies for Enhancement in Food Production	5
	Microbes in Human Welfare	4
Total		14 Marks
Unit IV: Biotechnology	Biotechnology: Principles & Processes	5
	Biotechnology & Its Applications	5
Total		10 Marks
Unit V: Ecology	Organisms & Populations	3
	Ecosystem	3
	Biodiversity & Conservation	3
	Environmental Issues	3
Total		12 Marks

PDF: ISC 12th Biology Marks Distribution 2026 Chapter-Wise

The ISC Biology exam for 2026 consists of a 70-mark theory paper and a 30-mark practical exam. The theory paper includes a mix of MCQs, short answers, and long descriptive questions, along with compulsory diagrams. Using this blueprint wisely can make exam preparation smoother and improve overall scoring potential.

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