Solved CBSE Class 12 Biology Term-2 Paper 2021-22

About this paper

This is the CBSE Class 12 Biology (Theory) Term-2 question paper from the 2021-22 session, Q.P. code 57/4/3 (Series AABB2/4, Set 3). It carries 35 marks, allows 2 hours plus 15 minutes of reading time, and has 13 compulsory questions in three sections: six two-mark questions, six three-mark questions and one five-mark case-based question. The case-based question offers a choice between Bt and non-Bt cotton yield data and the plasmid vector pBR322. Several questions are built around graphs, including population growth curves and a species–area plot, and internal choices are given in some questions. This copy has the questions only, without solutions.

Exam

CBSE Class 12

Subject

Biology

Year

2022

Paper code

57/4/3

Maximum marks

35

Time allowed

2 hours + 15 min reading

Questions

13

Pages

8

Answers included

No, questions only

Paper pattern

• Section A

  12 marks

  6 questions of 2 marks each; internal choice in some

• Section B

  18 marks

  6 questions of 3 marks each; internal choice in one

• Section C

  5 marks

  1 case-based question of 5 marks, with a choice of two cases

Topics covered

• Human health and disease
• Immunity and vaccines
• Microbes in human welfare
• Biocontrol agents
• Organisms and populations
• Biodiversity and conservation
• Biotechnology principles and processes
• Biotechnology and its applications

Questions from this paper

1. What are interferons? State their role in the treatment of cancer.
2. Explain, giving two reasons, how the immune response produced by a vaccine is different from that produced by an antitoxin in humans.
3. Why are predators considered to be 'prudent' in nature? Explain.
4. With the help of a storyboard or a flowchart only, explain all the stages of how human insulin is produced through r-DNA technology.
5. How did Dr. David Tilman experimentally relate the stability of a community to its species richness? Explain.
6. Bacillus thuringiensis plays an important role in Integrated Pest Management. Explain how, and name any two crops that are efficiently protected from pests.