Question No:1

In the context of genetic material, nucleotide consists of

[A] N-base, Ribose sugar, Phosphate group
[B] N-base, Hexose sugar, Phosphate group
[C] Nucleoside + Phosphate
[D] Both (a) and (c)



Question No:2

Uracil is associated with which sugar?

[A] Generally Deoxyribose
[B] Sometimes Ribose
[C] Only ribose
[D] Hexose



Question No:3

5 – end of ribose sugar bears

[A] N-base
[B] Deoxyribose
[C] Phosphate group
[D] Hydroxyl group



Question No:4

3^‘ end of the polynucleotide chain bears

[A] Phosphate group
[B] Hydroxyl group
[C] Methyl group
[D] Nitro group



Question No:5

In RNA, every nucleotide residue has an additional _____ group present at _____ position of ribose

[A] PO₄^3- 3^‘
[B] OH ^– ,3
[C] OH ^– ,2
[D] OH^–-,2^‘



Question No:6

Thymine can also be designated as

[A] 3 – Methyl uracil
[B] 2 – Methyl uracil
[C] 4 – Methyl uracil
[D] 5 – Methyl Uracil



Question No:7

J.D. Watson and F.H. Crick utilized X-ray diffraction data produced by

[A] Rosalind Wilkins and Maurice Franklin
[B] Maurice Wilkins and Rosalind Franklin
[C] Sutton and Boveri
[D] None of the above



Question No:8

Erwin Chargaff found that

[A] Ratios of adenine and cytosine and thymine and guanine are constant.
[B] Ratios of adenine and thymine and guanine and cytosine are constant.
[C] Ratios of adenine and guanine and thymine and cytosine are constant.
[D] Ratios of adenine – guanine and thymine – cytosine are constant.



Question No:9

DNA has two strands which are _____ to each other.

[A] supplementary
[B] complementary
[C] opposite
[D] perpendicular



Question No:10

The backbone of DNA double helix consists of

[A] Sugar-Base
[B] Sugar-Phosphate
[C] Sugar-Hydroxyl group
[D] Sugar-Methyl group



Question No:11

Anti-parallel polarity is exhibited by

[A] RNA
[B] t-RNA
[C] mRNA
[D] DNA



Question No:12

Which of the following holds true in case of DNA?

[A] A = T
[B] Adenine forms two H-bond with thymine
[C] Adenine forms one π bond with thymine
[D] Both (a) and (b)



Question No:13

Three H-bonds is exhibited by which DNA bases in double helix structure?

[A] Adenine, Guanine
[B] Guanine, Cytosine
[C] Cytosine; Thymine
[D] Adenine, Thymine



Question No:14

Double helix model of DNA has a pitch of

[A] 0.34 nm
[B] 3.4 nm
[C] 34 Å
[D] Both (b) and (c)



Question No:15

What confers additional stability to double helix model of DNA apart from the H-bond?

[A] One base pair provides inductive effect to the other.
[B] One base pair is stacked over the other.
[C] One base pair is perpendicular to another.
[D] One base pair interacts with another base pair via steric hindrance.