Principles of Inheritance and Variation — BIOLOGY STD 12 Science — Question

1. Explain any two defence mechanisms plants evolved against their predators.
2. How does predation differ from parasitism?

In relation to energy transfer in ecosystem, explain the statement "10kg of deer's meat is equivalent to 1kg of lion's flesh".

Write the mode of pollination in Vallisneria and water lily. Explain the mechanism of pollination in Vallisneria.

With which type of reproduction do we associate the reduction division? Analyse the reasons for it.

A large number of married couples the world over are childless. It is shocking to know that in India the female partner is often blamed for the couple being childless.
Why in your opinion the female partner is often blamed for such situations in India?

A large number of married couples the world over are childless. It is shocking to know that in India the female partner is often blamed for the couple being childless.

1. Why in your opinion the female partner is often blamed for such situations in India? Mention any two values that you as a biology student can promote to check this social evil.
2. State any two reasons responsible for the cause of infertility.
3. Suggest a technique that can help the couple to have a child where the problem is with the male partner.

Plants raised through tissue cultures are clones of the ‘parent’ plant. Discuss the utility of these plants.

Agrobacterium tumefaciens is considered as a good cloning vector. Explain why?

What is detritus food chain?

Differentiate between two different types of pyramids of biomass with the help of one example of each.