1691. The enzyme responsible for forming the final phosphodiester bond between two DNA fragments during DNA replication is :

A. DNA-directed RNA polymerase
B. DNA Ligase *
C. DNA polymerase I
D. DNA polymerase III
E. Reverse transcriptase

1692. Thymine is formed by addition of a methyl group at carbon number 5 of :

A. Adenine
B. Cytosine
C. Guanine
D. Uracil *
E. Xanthine

1693. The following coenzyme is required for catabolism of pyrimidine bases :

A. ATP
B. AMP
C. NADH
D. NADPH *
E. FADH

1694. In primary hyperoxaluria excessive oxalates arises from :

A. Alanine
B. Cysteine
C. Glycine *
D. Oxaloacetate
E. Serine

1695. Glutamine analogues inhibit:

A. Amido transferase *
B. Folate reductase
C. Phosphoribosyl pyrophosphate (PRPP) synthase
D. Hypoxanthine-guanine phosphoribosyltransferase (HGPRT)
E. Adenine phosphoribosyltransferase (APRT)

1696. Nitrogen at position 1 of pyrimidine core comes from :

A. Aspartate *
B. Amide group of glutamine
C. ALPHA-Amino group of glutamine
D. Glutamate
E. Glycine

1697. Which of the following is an inhibitor of xanthine oxidase and used in treatment of gout ?

A. Allourinol *
B. Fluorodeoxyuridylate
C. Hypoxanthine
D. Orotic acid
E. Methotrexate

1698. A mutation that converts an amino acid codon to stop codon is :

A. Frame shift mutation
B. Missense mutation
C. Non-sense mutation *
D. Silent mutation
E. Transversion

1699. Ring closure of forminmidoimidazole carboxamide ribosy-5-phosphate yields the first purine nucleotide :

A. AMP
B. IMP *
C. XMP
D. ATP
E. GMP

1700. The finished result of purine catabolism in man is:

A. Hypoxanthine
B. Inosine
C. Urea
D. Uric acid *
E. Xanthine