111. One gene-one enzyme relationship was established for the first time in

A Salmonella typhimurium
B Escherichia coli
C Diplocococcus pneumoniae
D Neurospora crassa
Answer :   Neurospora crassa
Discuss Question

112. An environmental agent, which triggers transcription from an operon, is a

A regulator
B inducer
C depressor
D controlling element
Answer :   inducer
Discuss Question

113. Telomerase is an enzyme which is a

A simple protein
B RNA
C ribonucleoprotein
D repetitive DNA
Answer :   ribonucleoprotein
Discuss Question

114. Nucleosome core is made of

A $${H_1},{H_2}A,{H_2}B$$    and $${H_3 }$$
B $${H_1},{H_2}A,{H_2}B,{H_4}$$
C $${H_1},{H_2}A,{H_2}B,{H_3}$$    and $${H_4 }$$
D $${H_2}A,{H_2}B,{H_3}$$   and $${H_4 }$$
Answer :   $${H_2}A,{H_2}B,{H_3}$$   and $${H_4 }$$
Discuss Question

115. Read the following four statements (A-D).
(A) In transcription, adenosine pairs with uracil.
(B) Regulation of lac operon by repressor is referred to as positive regulation.
(C) The human genome has approximately 50,000 genes.
(D) Haemophilia is a sex-linked recessive disease.
How many of the above statements are correct?

A Two
B Three
C Four
D One
Answer :   Two
Discuss Question

116. In an inducible operon, the genes are

A Always expressed
B Usually not expressed unless a signal turns them "on"
C Usually expressed unless a signal turns them "off"
D Never expressed
Answer :   Usually not expressed unless a signal turns them "on"
Discuss Question

117. Out of 64 codons, 61 codons code for 20 types of amino acid. It is called

A degeneracy of genetic code
B overlapping of gene
C wobbling of codon
D universility of codons
Answer :   degeneracy of genetic code
Discuss Question

118. One gene -one enzyme hypothesis was postulated by

A Hershey and Chase
B A. Garrod
C Beadle and Tatum
D R. Franklin
Answer :   Beadle and Tatum
Discuss Question

119. In a DNA percentage of thymine is 20% then what will be the percentage of guanine?

A 20%
B 40%
C 30%
D 60%
Answer :   30%
Discuss Question

120. In Escherichia coli, lac operon is induced by

A lactose
B promoter gene
C β-galactosidase
D I-gene
Answer :   lactose
Discuss Question


Practice More MCQ Question on Biology Section