ISC Class 12 Biology Important Questions for Last-Minute Revision

The ISC Class 12 Biology exam is a crucial milestone for students aiming to score well and secure admission to top universities. As the exam date approaches, revising efficiently becomes more important than covering everything in detail. To help you maximize your revision time, we have compiled a set of important questions based on past trends, frequently tested concepts, and examiner expectations.

These questions are designed to enhance your conceptual clarity and reinforce key topics such as genetics, human physiology, evolution, plant physiology, and biotechnology. Whether you are struggling with complex diagrams or tricky application-based questions, this list will help you stay on track and focus on what truly matters in the exam.

ISC Class 12 Biology Important Questions – Weightage

ISC Class 12 Biology Important Questions for Last-Minute Revision

1. Define the species-area relationship. What is the significance of the slope of regression? Show with the help of a graph.
2. Mention any two properties of DNA that make it an ideal genetic material.
3. State four measures taken by the government to control the high level of air pollution in cities.
4. Describe the process of DNA replication in prokaryotes.
5. Differentiate between infectious diseases and non-infectious diseases. Give two examples of each.
6. A snapdragon plant with red flowers was crossed with a plant with white flowers. It produced pink progeny in the F1 generation. Explain the principle of inheritance involved with the help of a Punnett square.
7. Mention any one symptom of elephantiasis. Name its causative agent.
8. Expand the following terms and explain them briefly: GIFT, ZIFT, RCH, ICSI, IVF.
9. If 10,000 Kcal energy is available at the level of producers, calculate the amount of energy at the level of secondary consumers.
10. Explain the steps involved in downstream processing in biotechnology.
11. What are the main objectives of plant breeding programmes?
12. How has biotechnology been useful in controlling nematode infection in plants? Explain the technique involved in this process.
13. Classify the methods of contraception. Write short notes on any two of the methods mentioned by you.
14. Give six features of the genetic code.
15. Explain the steps involved in artificial hybridization.
16. Draw a labelled diagram of the L.S. of the anatropous ovule.
17. Draw a labelled diagram of the T.S. of the anther.
18. Give two differences between Darwinism and the theory of mutation.
19. State the measures to be taken by the owner of a dairy farm to improve the quality of milk and the quantity of its production.
20. Give one difference between the following pairs: (i) Sites of maturation of B – Lymphocytes and T – Lymphocytes (ii) Sources of Opioids and Cannabinoids.
21. Briefly discuss any two methods by which plants avoid self-pollination.
22. Mention the location and the function of Leydig cells.
23. (i) What are vestigial organs? Give any one example of a vestigial organ in the human body.
    OR
    (ii) State Hardy Weinberg’s principle. Give a mathematical expression for this principle.
24. Riya went to the hospital to meet her sister who was undergoing some treatment. The hospital was crowded with patients suffering from various types of allergies, pneumonia, and Ascariasis. Name the disease that Riya is most likely to get infected with. Give one reason for your answer.
25. State the steps involved in the process of gene therapy for the treatment of ADA-deficiency.
26. In recent years, there has been a large-scale loss of biodiversity. Mention four ways in which humans are responsible for it.

Preparing for the ISC Class 12 Biology board exam can be overwhelming, but focusing on important topics and revising key concepts can make a significant difference. Understanding genetics, biotechnology, plant physiology, and ecology is crucial for scoring well. Additionally, practicing diagrams, learning the principles of inheritance, and revising important definitions can enhance your performance. Utilize this last-minute revision guide to streamline your preparation and boost your confidence before the exam. Stay calm, revise effectively, and give your best!

Also Check:

ISC Class 12 Biology Syllabus 2024-25

ISC Board Class 12 Biology Sample Paper 2025

ISC Class 12 Biology 2024 Question Paper with Solutions