CBSE 12th Biology Exam Pattern 2026 – Check Marking Scheme
Table of Contents
The CBSE Class 12 Biology Exam Pattern 2026 provides a clear understanding of the question paper format and structure, which aids in board exam preparation. The biology theory paper is divided into five sections (A - E) that assess different skills e.g. conceptual knowledge, application of knowledge, analysis, and interpretation. Each section has a variety of question types with varying marks, such as multiple choice, very short, short, case-based, and long answer questions.
The latest guidelines from CBSE 12th Exam Pattern 2026 specify that the biology theory exam is worth 70 marks and the practical exam is worth 30 marks, totalling 100 marks. There are questions from all units in the NCERT syllabus, with 33% internal choices and varying weightage of each unit.
Before you start preparing for the CBSE Class 12 Biology Exam 2026, make sure you are familiar with the exam pattern so that you can manage your time in the exam and focus on more high weightage topics to maximize your final score. Below is a more detailed explanation of the exam pattern.
Also Read: CBSE 12th Biology Syllabus 2026
CBSE 12th Biology Exam Pattern 2026 - Section Wise
The CBSE Class 12 Biology theory paper 2026 is worth 70 marks and is split into five major units. Genetics and evolution have the maximum weightage of 20 marks. Reproduction has the second-highest weightage, consisting of 16 marks. The remaining units, Biology, Human Welfare, and Biotechnology, are worth 12 marks each, while Ecology and Environment is worth 10 marks overall. To obtain your highest possible overall mark in your biology board examination, you will need spend time and focus more on the units with the highest weightage.
|
Unit |
Title |
Chapters |
Marks |
|
VI |
Reproduction |
Chapter 2: Sexual Reproduction in Flowering Plants Chapter 3: Human Reproduction Chapter 4: Reproductive Health |
16 |
|
VII |
Genetics and Evolution |
Chapter 5: Principles of Inheritance and Variation Chapter 6: Molecular Basis of Inheritance
|
20 |
|
VIII |
Biology and Human Welfare |
Chapter 8: Human Health and Diseases Chapter 10: Microbes in Human Welfare Microbes in food processing, industrial production, sewage treatment, energy generation and microbes as bio-control agents and bio-fertilizers. Antibiotics; production and judicious use. |
12 |
|
IX |
Biotechnology and its application |
Chapter 11: Biotechnology - Principles and Processes Chapter 12: Biotechnology and its Applications |
12 |
|
X |
Ecology and Environment |
Chapter 13: Organisms and Populations Chapter 14: Ecosystem Chapter 15: Biodiversity and its Conservation |
10 |
Also Read: CBSE 12th Admit Card 2026
CBSE 12th Biology Marking Scheme 2026
The CBSE Class 12 Biology Marking Scheme 2026 is intended to assess students' conceptual understanding, analytical thinking, and application of knowledge. The theory paper is worth a total of 70 marks and is divided into five sections - A to E, which contain a total of 33 questions in various formats. The question paper will include some combination of MCQs, very short, short, case-based, and long answer type questions with internal choices available for some of the questions. In addition to the theory exam, you are also required to give a practical examination worth 30 marks, making the subject total 100 marks.
|
Section |
Type of Question |
No of Questions |
Total Marks |
|
A |
Multiple-Choice Questions (MCQs)/Assertion-Reasoning |
16 |
1 x 16 = 16 |
|
B |
Short Answer Questions |
5 |
2 x 5 = 10 |
|
C |
Short Answer Questions |
7 |
3 x 7 = 21 |
|
D |
Case-based/Source-based/Passage-based/ Integrated Assessment Questions |
2 |
4 x 2 = 8 |
|
E |
Long Answer Questions |
3 |
5 x 3 = 15 |
|
|
TOTAL |
|
70 |
|
|
Practical: |
|
|
|
|
Identification/Familiarity with the apparatus |
|
5 |
|
|
Written test (Based on given / prescribed practicals) |
|
10 |
|
|
Practical Records |
|
5 |
|
|
Viva |
|
10 |
|
|
TOTAL |
|
30 |
Also Read: CBSE 12th Sample Papers 2026
CBSE 12th Biology Unit-Wise Marking Scheme 2026
The CBSE Class 12 Biology Unit Wise Marking Scheme 2026 is divided into five key units, with a total of 70 marks. Genetics and Evolution has the highest weightage (20%), followed by Reproduction (16%). Biology and Human Welfare, as well as Biotechnology and Its Applications, each contribute 12%, with Ecology and Environment contributing 10%. Understanding this distribution helps you to effectively manage your study time, focusing more on subjects that carry a higher weight to improve your overall exam performance. Examining the CBSE 12th Biology unit-wise marking scheme is essential. Once you understand the biology marking scheme, it will be easy for you to allocate the appropriate amount of time to each topic. Given below is an idea about the CBSE 12th Biology Unit- Wise Marking Scheme 2026:
|
Unit |
Title |
Chapters |
Weightage |
|
VI |
Reproduction |
Chapter 2: Sexual Reproduction in Flowering Plants Chapter 3: Human Reproduction Chapter 4: Reproductive Health |
16% |
|
VII |
Genetics and Evolution |
Chapter 5: Principles of Inheritance and Variation Chapter 6: Molecular Basis of Inheritance
|
20% |
|
VIII |
Biology and Human Welfare |
Chapter 8: Human Health and Diseases Chapter 10: Microbes in Human Welfare Microbes in food processing, industrial production, sewage treatment, energy generation and microbes as bio-control agents and bio-fertilizers. Antibiotics; production and judicious use. |
12% |
|
IX |
Biotechnology and its application |
Chapter 11: Biotechnology - Principles and Processes Chapter 12: Biotechnology and its Applications |
12% |
|
X |
Ecology and Environment |
Chapter 13: Organisms and Populations Chapter 14: Ecosystem Chapter 15: Biodiversity and its Conservation |
10% |
Also Read: CBSE 12th Biology Deleted Syllabus 2026
How to Use CBSE 12th Biology Exam Pattern 2026?
Understanding the format of the CBSE 12th Biology exam is one thing, but knowing how to use it to your advantage will help you study effectively and achieve the best possible score. The following is how to benefit from the CBSE 12th Biology Exam Pattern 2026:
- Focus on units with the highest marks, such as Genetics and Evolution (20%) and Reproduction (16%).
- The paper is divided into Sections A through E, so practice answering past year papers and sample questions in this format to become acquainted with the question patterns-MCQ, case-based, and long answers, among others.
- Use the pattern to plan how much time you'll spend in each section. Essentially, it is recommended to allow more time for long and case-based questions while less time for MCQ and very short answers, etc.
- Pay attention to the internal choice questions. Only 33% percent of the internal exam choices will be available for the CBSE 12th Biology Exam. Therefore, rather than deciding which option you would perform better on the test, practice both answers and work on the one you feel most confident about.
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