Class 12 BiologyImportant Questions for Board Exams

Why is sexual reproduction evolutionarily advantageous over asexual reproduction?

Describe double fertilisation in angiosperms. What is its significance?

Draw a well-labelled diagram of a mature embryo sac of an angiosperm.

Draw a diagram of the male reproductive system and label any five parts.

Describe the menstrual cycle. What are the roles of FSH and LH?

What is IVF? Describe the steps involved.

What is amniocentesis? Why is it banned in India for sex determination?

Explain the inheritance of ABO blood groups in humans. Why is it an example of codominance and multiple allelism?

What is crossing over? What is its significance?

Explain the lac operon model of gene regulation in E. coli. Distinguish between inducible and repressible operons.

Describe the semi-conservative mode of DNA replication. Who proved it experimentally?

Explain Hardy-Weinberg principle. What are the forces that disturb this equilibrium?

What is industrial melanism? How does it support Darwin's theory?

What is the difference between innate and acquired immunity? Explain with examples.

How does HIV cause AIDS? Describe the stages of HIV infection.

What is tissue culture? What are its advantages in plant breeding?

What is biofortification? Give two examples of biofortified crops.

Explain the process of sewage treatment. Distinguish between primary and secondary treatment.

What are biofertilizers? Give two examples and their uses.

What are restriction enzymes? How do they work? Give one example.

Describe the steps involved in recombinant DNA technology.

How was human insulin produced using genetic engineering? Why was this important?

What is gene therapy? Explain with the example of ADA deficiency.

Distinguish between exponential and logistic population growth. Draw and explain the graphs.

What is the difference between predation and parasitism? Give one example of each.

Explain the 10% law of energy transfer. Why is the pyramid of energy always upright?

What is decomposition? What are the steps involved?

What is biodiversity? Explain the types of biodiversity loss. What are the major causes?

Distinguish between in situ and ex situ conservation with examples.