CBSE Class 12 Biology Sample Paper 2021 Set 04

Biology
Download PDF

Find the CBSE Class 12 Biology Sample Paper 2021 Set 04 right below. We offer standard Class 12 Biology sample papers packed with detailed solutions for the 2026-27 term, following rules set by CBSE, NCERT, and KVS. Practice these model tests to build confidence and understand fresh marking trends.

CBSE Class 12 Biology Sample Question Papers

Our Class 12 Biology model papers are important for understanding the weightage of different chapters and the difficulty level of expected questions. By solving these guess papers Class 12 students can identify weak areas and improve time management. We also suggest referring to our Class 12 Biology Question Papers of previous years to further strengthen your exam preparation.

Biology Sample Papers for Class 12 (2026-27)

Section – A
 
1. A tissue, of a tobacco plant, infected with TMV was used to obtain a new plant. Identify the technique used and reason out the possibility of obtaining a new healthy plant.
 
2. State a method of cellular defense which works in all eukaryotic organisms 1
 
3. In case of an infertile couple, the male partner can inseminate normally but the mobility of sperms is below 40 percent. Which kind of ART is suitable in this situation to form an embryo in the laboratory conditions, without involving a donor?
 
4. Write the two components of the first artificial recombinant DNA molecule constructed by Cohen and Boyer.
 
5. A cross was carried out between two pea plants showing the contrasting traits of height of the plant. The result of the cross showed 50% of parental characters.n Name the type of cross.
 
Section B
 
6. The alarming population growth is leading to scarcity of basic requirements. Suggest with reasons, any two population control measures other than contraception to address the situation.
 
7. During a cytological study conducted on the chromosomes of the insects, it was observed that only 50% of the sperms had a specific structure after spermatogenesis. Name the structure and write its significance in sex determination of insects.
 
8. To reduce the percentage of population suffering from hunger and malnutrition, microbes are grown on a large scale to act as food supplements. Mention any two microbes used as food supplement and suggest their role.
 
OR
 
Success rate of artificial insemination in cattle is fairly low. Identify any other technique to improve the successful production of hybrids. State two advantages of this technique.
 
9. (a) A patient who had an organ transplant was given cyclosporin– A. Mention the microbial source and state the reason for administration of this bioactive molecule.
(b) Bottled fruit juices bought from the market are clearer as compared to those made at home. Give reason.
 
10. Evaluate the effect of loss of biodiversity in a region. Mention any four such effects.
 
Section C
 
11. Draw the diagram of microsporangium of an Angiosperm and label any four parts State the function of its innermost wall layer.
 
12. Give reason : -
(a) A liverwort plant is unable to complete its life cycle in a dry environment.
(b) Number of male gametes produced is much more than the female gametes produced.
(c) Organisms exhibiting external fertilization show great synchrony between the sexes and release a large number of gametes into surrounding medium.
 
13. (a) Name the different gases contained in the flask used as an experimental setup by S.L. Miller.
(b) On the basis of composition of gases in this experiment, what was the condition in the flask?
(c) Write the conclusion drawn from this experiment.
 
14. When a snapdragon plant bearing pink colour flower was selfed, it was found that, 69 plants were having red coloured flowers. What would be the number of plants bearing pink flower and white flower. Show with the help of Punnett square. Identity the principle of inheritance involved in this experiment
 
15. Refer to the figure given below and answer the questions that follow:

CBSE Class 12 Biology Sample Paper 2021 Set D 1

(a) Explain the process by which Tasmanian wolf evolved.
(b) Name the process that has resulted in evolution of wolf and Tasmanian wolf.
(c) Compare and contrast the two animals shown?
 
16. Your classmate complains of headache and cough. On the basis of certain symptoms, the doctor confirms that he is suffering from Pneumonia and not common cold. List these symptoms. Mention any two precautions to be followed to prevent the spread of this disease.
 
17. Cow dung and water is mixed and this slurry is fed into the biogas plant for digestion by microbes. The person performing the process shares that there is no need to provide any inoculum for it. Give reason. What is the role of microbes at the source? Under which condition will they be most active and effective?
 
18. A person is born with a weakened immune system due to deficiency of an enzyme which is a hereditary disease. Suggest a technique to completely cure this disease, identify the deficient enzyme and explain the technique used, for cure.
 
19. A doctor prescribed morphine as a sedative and pain killer to your cousin who had undergone a surgery. Even after recovery, he indiscriminately took the medicines and later craved for the same. What do you conclude about his
condition? What measures will you suggest to him to overcome this problem? Briefly explain any two.
 
20. Given below is the diagram of agarose gel kept under UV light:
CBSE Class 12 Biology Sample Paper 2021 Set D 2
(a) Mention the positive and negative terminals.
(b) What is the charge carried by DNA molecule and how does it help in its separation?
(c) How are the separated DNA fragments finally isolated?
 
OR
 
CryIAbis introduced in a plant to prevent infestation by corn borer.
(a) What is the resultant plant referred as?
(b) Summarize the action of the gene introduced
 
 
21. (a) In pBR322, foreign DNA has to be introduced in tetRregion. From the restriction enzymes given below, which one should be used and why: PvuI, EcoRI, BamHI
(b) Give reasons, why the other two enzymes cannot be used.
 


Please click on below link to downloadCBSE Class 12 Biology Sample Paper 2021 Set D

Free study material for Biology

Exam Preparation Sample Paper for Class 12 Biology CBSE Class 12 Biology Sample Paper 2021 Set 04

Download Sample Paper: CBSE Class 12 Biology Sample Paper 2021 Set 04 (Class 12 Biology)

Easily download the CBSE Class 12 Biology Sample Paper 2021 Set 04 online to strengthen your final preparations. Mastering the official paper structure is vital for Class 12 students seeking higher marks. We recommend solving these updated Biology sample papers to practice anticipated question formats. Download the PDF format for flexible offline drills, ensuring you practice under true test conditions.

Benefits of Practicing Class 12 Biology Sample Papers

  • Original Question Sets: Provides diverse practice questions for Biology to expand your problem-solving range.
  • Exam Structure Mastery: Understand exact mark allocations and question architectures relevant to Class 12 evaluations.
  • Gap Analysis: Check your accuracy levels to identify challenging Class 12 Biology concepts requiring deeper review.
  • Exam Completion Skills: Routine problem sets for Class 12 Biology train you to manage test duration efficiently without stress.

Post-Practice Strategy for Class 12 Biology

  1. Self-Evaluation: Score your answers using the official guidance found in the Biology Sample Paper PDF.
  2. Targeted Correction: Class 12 pupils must re-solve questions answered incorrectly to master the correct method.
  3. Core Review: Look up challenging questions inside the NCERT book for Class 12 Biology to build solid fundamentals.
  4. Regular Practice: Solve extra Biology sample modules online to maximize preparedness for upcoming CBSE evaluations.

FAQs

Where can I download the PDF for CBSE Class 12 Biology Sample Paper 2021 Set 04?

You can download the complete PDF for CBSE Class 12 Biology Sample Paper 2021 Set 04 for free from StudiesToday.com. Our resources for Class 12 Biology are updated for the latest academic session and follow the official exam pattern.

Are solutions provided for CBSE Class 12 Biology Sample Paper 2021 Set 04?

Yes, CBSE Class 12 Biology Sample Paper 2021 Set 04 comes with detailed, teacher-verified solutions. We have provided step-by-step answers for Biology to help students of Class 12 understand correct methodology and marking scheme.

How can practicing CBSE Class 12 Biology Sample Paper 2021 Set 04 help in exam preparation?

Practicing this Biology paper helps in time management and identifying important topics. For Class 12, solving mock papers is the best way to gain confidence and reduce exam-day anxiety.

Is the CBSE Class 12 Biology Sample Paper 2021 Set 04 accessible on mobile and tablets?

Yes, all our study materials for Class 12 Biology are provided in a mobile-friendly PDF format. You can easily download CBSE Class 12 Biology Sample Paper 2021 Set 04 on your mobile device.