Following statements are regarding to enzymatic processing of benzo(a)pyrene to a more potent mutagen and carcinogen.

A. Liver enzymes, particularly P-450 enzymes, modify benzo(a)pyrene in a series of reactions, producing 7,8-diol-9,10-epoxide, a highly potent mutagenic species that reacts with DNA primarily at the N2 atom of a guanine base.

B. The adduct, (+)-trans-anti-B(a)P-N2-dG, causes polymerase to insert an A rather than a C opposite the modified G base. Next time the DNA is replicated, a T will be inserted opposite the A, and the mutation will be complete.

C. Potent mutagen majorly causes conversion of guanine (G) to thymine (T) bases, a transition mutation.

D. When this potent mutagen applied to cultured bronchial epithelial cells, activated benzo(a)pyrene induces many mutations, including activating mutations at codons 175, 248, and 273 of the p53 gene.

Which of the following statements are correct?

TLS Online TPP Program

#Question id: 13075

#Unit 13. Methods in Biology

Radioisotopes must be used in RFLP and RAPD markers

TLS Online TPP Program

#Question id: 13076

#Unit 13. Methods in Biology

Restriction fragment length polymorphism denotes that a single restriction enzyme produces fragments of different lengths from the same stretch of genomic DNA of different strains of a species or from different related species. RFLPs are detected as follows:

i.  Large molecular weight genomic DNA is isolated from several strains or related species;

ii.  The fragments in these digests are separated through electrophoresis

iii.  These 'DNAs are then digested with a selected restriction enzyme

iv.  Exposed to a suitably radio-labelled appropriate DNA probe under conditions favouring DNA: DNA hybridization

v.  The resulting gel lanes are transferred and fixed to a suitable solid support and

vi.   The free probes are removed

vii.  The fragments to which the probe has hybridized are detected by filming them as distinct bands on a suitable photofilm through autoradiography.

TLS Online TPP Program

#Question id: 13077

#Unit 13. Methods in Biology

The DNA probes for RFLP may NOT be obtained from

TLS Online TPP Program

#Question id: 13078

#Unit 13. Methods in Biology

RFLPs have several unique advantages except this one;

TLS Online TPP Program

#Question id: 13079

#Unit 13. Methods in Biology

Name of that sophisticated equipment which used to the oligonucleotide, that serve as a primer in RAPDs is usually obtained by in vitro DNA synthesis,

TLS Online TPP Program

#Question id: 13080

#Unit 13. Methods in Biology

In RAPDs amplification will take place only of those regions of the genome that have the