HSC Science (General) 12th Standard Board Exam - Maharashtra State Board Important Questions

What is a test cross?

Answer the following questions related to sex determination in human beings:
i. What is sex chromosome?
ii. How many pairs of chromosomes are present in human beings?
iii. How is the sex of the human offspring determined?
iv. Draw a diagram depicting sex determination in man.

Explain the mechanism of sex determination in birds.

What is the reason for the 21^st trisomy?

Give reasons for the development of Turner’s syndrome and also mention its symptoms.

Identify chromosomal disorder caused due to non-disjunction of the 21^st number of chromosomes and enlist its symptoms.

______ enzymes are used as biological scissors in r-DNA technology.

What is Bacteriophage?

What is degeneracy of genetic code?

How t-RNA act as an adapter molecule?
Explain in detail with the help of a diagram.

Why water acts as a thermal buffer?

Define the following:

Hygroscopic water

Why water is called as ‘Elixir of Life’?

What is a grand period of growth?

A farmer is fed up of weeds in his Wheat farm. Which of the following chemicals he can use to overcome the problem?

Buyers often complain that a particular fruit merchant uses some chemical to ripen fruits in his shop.

Name the chemical he must be using to do so.

Why is ABA known as antitranspirant?

A gardener wants to give bushy appearance to plants in our college campus.

1. What should he do to achieve the same? 
2. Which property of phytohormones he must be aware of?

Write the name of______

1. First hormone discovered in plants.
2. Biological name of fungus from which Gibberellins were first isolated. 
3. The name given to the first cytokinin by Skoog and Miller.

Write the name of Hormone that can overcome the requirement of vernalization.