Science (English Medium) इयत्ता १२ - CBSE Question Bank Solutions for Biology

The test-tube baby programme employs which one of the following techniques?

The first case of IVF-ET technique success, was reported by ______.

Which of the following is a non-medicated intrauterine device (IUD)?

The year 2003 was celebrated as the 50th anniversary of discovery of ______.

Chemically, RNA is (i) reactive and (ii) stable as compared to DNA.

In ET technique embryo is transferred into ______.

In which of the following ARTs, does in vivo fertilisation occur?

ZIFT is transfer of ______.

Mark the odd one.

A cross is made between tall pea plants having green pods and dwarf pea plants having yellow pods. In the F2 generation, out of 80 plants how many are likely to be tall plants?

Read the following and answer from given below:

Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are the two types of nucleic acids found in the living system. DNA acts as the genetic material in most organisms. Although RNA also acts as genetic material in some organisms.

In which of the following organisms, RNA acts as genetic material?

Read the following and answer from given below:

Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are the two types of nucleic acids found in the living system. DNA acts as the genetic material in most organisms. Although RNA also acts as genetic material in some organisms.

What is the reason for the additional stability of DNA in comparison to RNA?

Read the following and answer from given below:

Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are the two types of nucleic acids found in the living system. DNA acts as the genetic material in most organisms. Although RNA also acts as genetic material in some organisms.

Which of the following criteria a molecule must fulfill to act as genetic material?

Mention the primary aim of the “Assisted Reproductive Technology” (ART) programme.

Males in whom testes fail to descend to the scrotum are generally infertile. Why?

Briefly explain IVF and ET What are the conditions in which these methods are advised?

What are the Assisted Reproductive Techniques practised to help infertile couples? Describe any three techniques.

What is the cross between the progeny of F₁ and the homozygous recessive parent called? How is it useful?

Name any three viruses which have RNA as the genetic material.

During the course of evolution why DNA was chosen over RNA as genetic material? Give reasons by first discussing the desired criteria in a molecule that can act as genetic material and in the light of biochemical differences between DNA and RNA.