1681. The synthesis of DNA from RNA template is catalyzed by :

A. DNA-polymerase 1
B. DNA-polymerase II
C. DNA-polymerase IH
D. Reverse transcriptase *
E. Reverse polymerase

1682. During transcription unwinding of DNA is catalyzed :

A. DNA polymerase
B. Helicase *
C. RNA Polymerase
D. RH factor
E. Sigma factor

1683. cAMP leads to phosphorylation of many proteins and activation of enzymes . Which one of the following is deactivated by phosphorylation ?

A. cAMP dependent protein kinase
B. Phosphrylase kinase
C. Phosphorylase
D. Inhibitor I
E. Glycogen synthase *

1684. Direction of DNA synthesis is :

A. 5′-3′ direction *
B. 3′-5′ direction
C. 5′-2′ direction
D. 2′-5′ direction
E. None of the above

1685. Proof reading during replication is the function of :

A. DNA polymerase I
B. RNA polymerase I
C. DNA ligase
D. DNA polymerase III *
E. Helicase

1686. The number of termination codons is :

A. 1
B. 2
C. 3 *
D. 4
E. 5

1687. Non- coding sequences in a gene are knwon as :

A. Cistrons
B. Nonsense codons
C. Introns *
D. Exons
E. Protomers

1688. Active gout is generally associated with :

A. A diet low in nucleic acids
B. Increased intestinal xanthine oxidase activity
C. Increased orotic acid synthesis
D. Smoking
E. Urate crystals in joint fluids *

1689. Which of the following is a source of atom of purine ring ?

A. Arginine
B. Glycine *
C. Isoleucecine
D. Leucine
E. Methionine

1690. In Leisch-Nyhan’s syndrome there is deficiency of :

A. Arginase
B. Carbonyl phosphate synthase
C. Hypoxanthine guanine phosphoribosyl transferase *
D. Phosphor ribosyl glutamyl amido transferase
E. Xanthine oxidase