CBSE Class 12 Biology Sample Paper 2020 Solved Set A

Read and download the CBSE Class 12 Biology Sample Paper 2020 Solved Set A, designed by expert teachers according to the latest 2025-26 curriculum and examination pattern issued by CBSE, NCERT, and KVS. These Class 12 Biology sample papers include detailed step-by-step solutions, helping students to practice and evaluate their performance against the most recent marking schemes.

Solved Sample Paper for Class 12 Biology PDF

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.

Class 12 Biology Sample Paper with Solutions

CBSE Class 12 Biology Sample Paper 2020 Solved Set A. CBSE issues sample papers every year for students for Class 12 board exams. Students should solve the CBSE issued sample papers to understand the pattern of the question paper which will come in class 12 board exams this year. The sample papers have been provided with marking scheme. It’s always recommended to practice as many CBSE sample papers as possible before the board examinations. Sample papers should be always practiced in examination condition at home or school and the student should show the answers to teachers for checking or compare with the answers provided. Students can download the sample papers in pdf format free and score better marks in examinations. Refer to other links too for latest sample papers.

Section A

1 Scientists have succeeded in recovering healthy sugarcane plants from a diseased one

a) Name the part of the plant used as explant by the scientists

b) Name this technology used for crop improvement.

2 In case of an infertile couple, the female partner produces normal ovum but is unable to provide suitable environment for further development of embryo.Which kind of ART is suited in this situation to form a foetus? 

3 Name the muscular and glandular layer of human uterus.

4 List two advantages that a mycorrhizal association provides to the plant.

5 Name the product of fertilisation that forms the kernel of coconut. How does the kernel differ from coconut water?

Section B

6 What is ‘The Evil Quartet’ that has caused biodiversity loss?

7 Why have certain regions been declared as biodiversity ‘hotspots by environmentalists of the world? Name any two hotspot regions of India.

8 What is the inheritance pattern observed in the size of starch grains and seed shape of Pisum Sativum? Work out the monohybrid cross showing the above traits. How does this pattern of inheritance deviate from that of Mendelian law of dominance?

 

9 a) Name the natural source of Agarose. Mention one role of agarose in biotechnology.
b) What was the specialty of the milk produced by the transgenic cow, Rosie?
 
10 Discovery of lobefins is considered very significant by evolutionary biologists. Explain 2
 
Section C
 
11 List any three outbreeding practices carried out to breed domestic animals. Explain the importance of each one listed.
 
OR
Trace the events in human body that occur to cause immunodeficiency, when HIV gains entry into the body.
 
12 (a) Baculoviruses are an excellent candidate for integrated pest management in an ecologically sensitive area. Explain giving two reasons.
(b) What is organic farming? Why is it suggested to switch over to organic farming?
 
13 (a) In a pond , there were 20 Hydrilla plants. Through reproduction, 15 new Hydrilla plants were added in a year. Calculate the birth rate of the population.
(b) List any four adaptations evolved in animals to adapt to their parasitic mode of life.
 
 
14 What is point mutation? Explain with the help of an example. 
 
15 i) What is accelerated eutrophication and how is it different from Eutrophication? Mention its consequence in the water body.
ii)A crane has DDT level as 5 ppm in its body. What would happen to the population of such birds? Give reasons.
 
 
16 (a) Correlate the codons on mRNA strand with the amino acids of a polypeptide translated
5’ – AUG ACC UUU CAC UUC GUG UAA – 3’……..mRNA
Met – Thr – Phe – His – Phe – Val ……..Translated polypeptide
Infer any four properties of genetic code with example from the above information
(b) In the genetic code for 64 amino acids, how many codons code for amino acids and how many do not?
 
17 Describe the hormonal control of spermatogenesis in a human male. 
 
18 a) Mention two strategies evolved in plants to prevent autogamy in flowers
b) Differentiate between the menstrual cycle and oestrous cycle.
 
19 a) Plasmid is a boon to biotechnology. Justify this statement quoting the production of human insulin as an example.
b) How is the insulin produced using biotechnology different from proinsulin secreted by functional human insulin gene, with the help of diagram?
 
 
20 a) Explain the process of charging of tRNA. Mention its role in transcription.
b) How do ribosomes in the cells act as factories for protein synthesis?
c) Describe initiation and termination phases of protein synthesis.


Please click the link below to download CBSE Class 12 Biology Sample Paper 2020 Solved Set A 


How to download CBSE Class 12 Biology Sample Paper 2020 Solved Set A in PDF?

Students can easily download the CBSE Class 12 Biology Sample Paper 2020 Solved Set A from our website to prepare for their upcoming examinations. To score high marks, it is important for Class 12 students to understand the exaact pattern as per which teachers design the question papers. We strongly suggest that you practice these latest sample papers for Biology and solve different types of questions that are expected to come this year. You can downloadin PDF format so that you can practice offline. We also recommend that Class 12 students solve these papers actual exam conditions at home.

Why should you solve CBSE Class 12 Biology Sample Paper 2020 Solved Set A?

Practicing these model papers has several benefits for Class 12 students:

  • New Question Bank: This set has fresh questions for Biology which are different from previous years.
  • Exam Pattern Knowledge: Solving more sets will help you to understand the weightage of each chapter in Class 12 and also the type of questions asked.
  • Identify Weak Areas: Comparing your score in each set to find out topics in Class 12 Biology for which you need hard work.
  • Speed and Accuracy: Attempting MCQ questions and long-form problems for Class 12 Biology makes you faster and better and you will be able to finish your exam on time.

What should you do after solving CBSE Class 12 Biology Sample Paper 2020 Solved Set A?

  1. Check Your Work: Match your answers with the solutions given by our teachers in the Biology Sample Paper PDF.
  2. Learn from Mistakes: Class 12 students should focus on the questions which you solved incorrectly and understand the error.
  3. Revision: If you find a question difficult you shoul refer to NCERT book for Class 12 Biology to understand concepts and then try the question again.
  4. Continuous Practice: Solve multiple sets of Biology sample papers from studiestoday.com to build confidence before the CBSE exams.
Where can I download the PDF for CBSE Class 12 Biology Sample Paper 2020 Solved Set A?

You can download the complete PDF for CBSE Class 12 Biology Sample Paper 2020 Solved Set A 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 2020 Solved Set A?

Yes, CBSE Class 12 Biology Sample Paper 2020 Solved Set A 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 2020 Solved Set A 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 2020 Solved Set A 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 2020 Solved Set A on your mobile device.