Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

What is the fundamental basis of biodiversity in biosphere?

How many pollen grains and ovules are likely to be formed in the anther and the ovary of an angiosperm bearing 25 microspore mother cells and 25 megaspore mother cells respectively?

Given below is a section of maize grain. Identify A and state its function.

Name and state the law of Mendel, which explains the expression of only one of the parental characters in the F, progeny of a monohybrid cross.

Why do pollen grains of some flowers trigger ‘sneezing’ in some people?

Directions: In the following questions, the Assertions (A) and Reason(s) (R) have been put forward. Read both the statements carefully and choose the correct alternative from the following:
Assertion: PCR can detect very low amounts of DNA and is now routinely used to defect HIV in suspected AIDS patient.
Reason: PCR is a powerful technique to identify many other genetic disorders.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
3. Assertion is correct but Reason is incorrect.
4. Both Assertion and Reason are incorrect.

Name the type of evolution that has resulted in the development of structures like wings of butterfly and bird. What are such structures called?

Name the historic convention on biological diversity held at Rio in 1992.

What do you understand by ecophene?

What is the branch of biology in which fossils are studied, called?