CBSE Class 12 Biology Important Questions 2024-24

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CBSE Class 12 Biology Important Questions 2024-25: The Central Board Of Secondary Education is going to hold the CBSE 12th Board Exam 2025 will be held in February 2024 in offline mode. The Board will release the detailed CBSE class 12 timetable 2025 in December 2024 on its official website. To score well, it is very important to know about the important questions or the repeated questions that have a high chance to come in the CBSE 12th Exam 2024. We have provided weightage-wise and chapter-wise CBSE Class 12 Biology important questions for the students so that they can ace their CBSE 12th preparation 2025.

Moreover, CBSE 12th Board exam 2025 students must also practice the CBSE class 12 previous year questions and CBSE class 12 sample papers daily to have more idea about the important and repeated questions of the CBSE 12th Biology Exam 2025.

CBSE Class 12 Biology Important Questions: High Weightage Questions

In this section, the high weightage carrying important questions that can come in the CBSE 12th Biology question paper are provided here. These questions are of 5 marks each. The students should focus on these questions importantly.

Question 1: Describe the experiment carried out by Hershey and Chase. Write the conclusion they arrived at.

Question 2: Trace the events from copulation to zygote formation in a human female.

OR,

Trace the development of a megaspore mother cell to the formation of mature embryo sac in a flowering plant.

Question 3: (a) What is a trophic level in an ecosystem? What is ‘standing crop’ with reference to it?

(b) Explain the role of the ‘first trophic level’ in an ecosystem.

(c) How is the detritus food chain connected with the grazing food chain in a natural ecosystem?

Question 4: What is “population” according to you as a biology student?

(b) “The size of a population for any species is not a static parameter.” Justify the statement with specific reference to fluctuations in the population density of a region in a given period of time.

Question 5: Explain menstrual cycle in human females.

(b) How can the scientific understanding of the menstrual cycle of human females help as a contraceptive measure?

Also Check: CBSE Class 12 Exam Pattern 2024-25

CBSE Class 12 Biology Important Questions: 3 Mark Questions

Here we have provided the important questions of CBSE 12th Biology exam 2024 that carry 3 marks each:

Question 1: Explain the roles of the following with the help of an example each in recombinant DNA technology:

(a) Restriction Enzymes (b) Plasmids

Question 2: List six advantages of “ex-situ” approach to conservation of biodiversity.

Question 3: Describe the formation of recombinant DNA by the action of EcoRI.

Question 4: Write two differences between Homo erectus and Homo habilis.

(b) Rearrange the following from early to late geologic periods: Carboniferous, Silurian, Jurassic.

Question 5: How has the development of bioreactor helped in biotechnology?

(b) Name the most commonly used bioreactor and describe its working.

CBSE Class 12 Biology Important Questions: 2 Marks Questions

Question 1: What is an allergy? Name the antibody responsible for it. Also, mention two chemicals released from the mast cells during an allergic reaction.
Question 2: Mention the role of histone proteins in the packaging of DNA to form the structure of chromatin fibre.
Question 3: (a) Differentiate between zoospore and zygote. (b) Which parts of the flower develop into perisperm and pericarp?
Question 4: State any three advanced methods of ex-situ conservation. In which way, do you think, are the advanced methods better than the traditional ex-situ methods?
Question 5: Give the binomials of two types of yeast and the commercial bioactive products they help to produce.

CBSE Class 12 Biology Important Questions: 1 Mark Questions

Some of the 1-mark questions in the CBSE class 12 Biology exam 2024 are as follows:

Question 1: An infertile couple was advised to undergo In vitro fertilization by the doctor. Out of the options given below, select the correct stage for transfer to the fallopian tube for successful results?

(a) Zygote only

(b) Zygote or early embryo upto 8 blastomeres

(c) Embryos with more than 8 blastomeres

(d) Blastocyst Stage

Question 2: Zoospores are the reproductive units to carry asexual reproduction in

(A) Chlamydomonas

(B) Spirogyra

(C) Yeast

(D) Rhizopus

Question 3: Micropropagation can be achieved by

(A) Self-pollination

(B) Asexual reproduction

(C) Tissue culture

(D) Vegetative propagation

Question 4: What are ‘flocs’, formed during secondary treatment of sewage?

Question 5: Name two diseases whose spread can be controlled by the eradication of Aedes mosquitoes.

CBSE Class 12 Biology Important Questions: Chapter-wise Weightage

Check out the chapter wise important questions of CBSE Class 12 Biology Exam:

Chapter 7 Genetics and Evolution

Question 1: State the two principal outcomes of the experiments conducted by Louis Pasteur on origin of life. (2 marks)

Question 2: State two postulates of Oparin and Haldane’s theory with reference to the origin of life. (2 marks)

Question 3: Write the hypothetical proposals put forth by Oparin and Haldane. (3 marks)

Chapter 1 Reproduction

Question 1: “The offsprings produced by asexual reproduction are referred to as clones”. Why? (2 marks)

Question 2: What are the two inherent characteristics of amoeba and yeast that favour asexual reproduction in them? (2 marks)

Question 3: Why can’t multicellular organisms reproduce by cell division? (2 marks)

Chapter 10 Microbes in Human Welfare

Question 1: Why is secondary wastewater treatment referred to as biological approach?

Question 2: What is the significance of antibiotics in medicine?

Question 3: Name the common trait shared between Clostridium butylicum, Lactobacillus and Aspergillus niger.

CBSE Class 12 Biology Important Questions: Exam Pattern

The CBSE Class 12 Biology exam will divide into two sections: theory (70 marks) and practical (30 marks), with the total marks of 100. The exam will be asked in both Multiple Choice Questions (MCQs) and Application-based questions. The duration for both theory and practical exams will be 3 hours in total. Refer to the table below to know about the type of questions to be asked in the CBSE 12th Biology question paper and the marking scheme along with the marks allotted to each type of question.

Prepare the answers for the above-mentioned CBSE Important Questions for Class 12 Biology. Students must not do suggestive study and must cover each and every topic. For more information on Education News stay tuned to CollegeDekho!