CBSE Class 12 Biology Exam 2026 Repeated Questions : In the final exam, the questions generally repeat from the important chapters like Reproduction, Genetics, Evolution, Human Health and Disease, Biotechnology, and Ecology. Solving the repeated questions will enable you to focus on key topics with high chances of coming again, helping in efficient revision and exam confidence. Knowing the CBSE 12th Biology 2026 repeated questions will also allow you to prioritize the key areas and allocate your preparation time wisely. If you can regularly solve these questions, you will be able to recognize the exam pattern, types of questions asked (e.g., diagram-based, short answers, long answers), and their difficulty level. Solving these questions will also help you get accustomed to answering questions within the time limit, improving speed and efficiency. Let's check out what the CBSE Class 12 Biology Exam 2026 Repeated Questions are.

Also Check CBSE Class 12 Biology Important Questions 2025-26

CBSE Class 12 Biology Exam 2026 Repeated Questions

Below, we have given chapter-wise the most repeated CBSE Class 12 Biology Questions that you can consider as the most important questions for the academic year 2025-26:

Chapter 2: Sexual Reproduction in Flowering Plants

• Angiosperms bearing unisexual flowers are said to be either monoecious or dioecious. Explain with the help of one example each.
• Draw a diagram of a mature microspore of an angiosperm. Label its cellular components only. OR Draw a labelled diagram of a mature pollen grain.
• Describe the process of megasporogenesis up to fully developed embryo sac formation in an angiosperm. (All India 2019)
• (i) Describe the sequence of the process of microsporogenesis in angiosperms. (ii) Draw a labelled diagram of a 2-celled final structure formed.

Chapter 3: Human Reproduction

• List the different parts of the human oviduct through which the ovum travels till it meets the sperm for fertilisation.
• Explain the role of pituitary and sex hormones in the process of spermatogenesis.
• Differentiate between menarche and menopause.

Chapter 4: Reproductive Health

• Our government has intentionally imposed strict conditions for MTP in our country. Justify giving a reason.
• At the time of Independence, the population of India was 350 million, which exploded to over 1 billion by May 2000. List any two reasons for this rise in population and any two steps taken by the government to check this population explosion.
• An infertile couple is advised to adopt a test tube baby program. Describe two principal procedures adopted for such technologies. (Delhi 2015) OR Explain the Zygote Intra Fallopian Transfer Technique (ZIFT). How is the Intra Uterine Transfer (IUT) Technique different from it?

Also Check CBSE Class 12 Biology Weightage 2026

Chapter 5: Principles of Inheritance and Variation

• Name the pattern of inheritance where the F1 phenotype

(i) resembles only one of the two parents.

(ii) does not resemble either of the two parents and is in between the two.

• Mention any two contrasting traits with respect to seeds in pea plants that were studied by Mendel.

Why did TH Morgan select Drosophila melanogaster to study sex-linked genes for his lab experiments?

• Linkage and crossing over of genes are alternatives to each other. Justify with the help of an example.

Chapter 6: Molecular Basis of Inheritance

• Why is RNA more reactive in comparison to DNA?
• Name the enzyme and state its property that is responsible for continuous and discontinuous replication of the two strands of a DNA molecule.
• Describe the structure of a nucleosome. (Delhi 2017)

Chapter 7: Evolution

• Name the type of evolution that has resulted in the development of structures like the wings of a butterfly and birds. What are such structures called?

Chapter 8: Human Health and Diseases

• ‘Prevention is better than cure’ is an apt slogan to safeguard adolescents from drug abuse. List any 6 steps that could be taken in this regard.

Chapter 10: Microbes in Human Welfare

• (i) How do organic farmers control pests? Give two examples.

(ii) State the difference in their approach from that of conventional pest control methods.

Chapter 11: Biotechnology- Principles and Processes

• Why is it not possible for an alien DNA to become part of a chromosome anywhere along its length and replicate normally?

Chapter 12: Biotechnology and its Applications

• Biopiracy should be prevented. State why and how?
• Mention any four benefits derived from transgenic animals

The above-mentioned repeated questions serve as an important tool for focused and strategic exam preparation. These questions are the most frequently asked concepts and topics mentioned in the CBSE Class 12 Biology Syllabus 2025-26 . Hope these above-mentioned questions will help you in your exam preparation.