The premature termination of polypeptide synthesis due to stop codon can be overcome via compensatory mutation in tRNA. This genetic phenomenon is called

(1) extragenic suppression

(2) intragenic suppression

(3) codon bias

(4) true reversion

Suppose, evolution on earth had occurred in such a way that there are 96 amino acids instead of 20. DNA has 12 different types of bases and DNA synthesis occurs in the same way as today. The minimum number of bases per DNA codon would be

(1) 12

(2) 8

(3) 2

(4) 3

Radioactive thymidene is fed to cells about to enter S-phase. It will make radioactive

(1) euchromatin

(2) heterochromatin

(3) Both (1) and (2)

(4) neither euchromatin nor heterochromatin

What would happen, if in a gene encoding a polypeptide of 50 amino acids, 25^th codon (UAU) is mutated to UAA?

(1) A polypeptide of 49 amino acids will be formed

(2) A polypeptide of 25 amino acids will be formed

(3) A polypeptide of 24 amino acids will be formed

(4) Two polypeptides of 24 and 25 amino acids will be formed

Which one of the following set meaning is not different?

Okazaki is known for his contribution to the understanding of

(1) transcription

(2) translation

(3) DNA replication

(4) mutation

The beginning of understanding genetic transformation in bacteria was made by

(1) Frederick Griffith

(2) Hershey and Chase

(3) Watson and Crick

(4) TH Morgan

If the total amount of adenine and thymine in a double-stranded DNA is 45%, the amount of guanine in this DNA will be

(1) 22.5%

(2) 27.5%

(3) 45%

(4) 55%

AUG codes for

(1) valine

(2) histidine

(3) phenylalanine

(4) methionine

In the lac operon model, lactose molecules function as:-

(1) inducers, which bind with the operator
gne

(2) repressors, which bind with the operator
gene

(3) inducers, which bind with the repressor
protein

(4) corepressors, which bind with repressors
protein