#Question id: 12529
#Unit 6. System Physiology – Plant
#Question id: 1520
#Unit 1. Molecules and their Interaction Relevant to Biology
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?
#Question id: 24610
#Unit 2. Cellular Organization
Choose which of the following statement is correct
#Question id: 4724
#Unit 8. Inheritance Biology
Which of the following are true about crossing over ?
#Question id: 24635
#Unit 2. Cellular Organization
In E.coli topoisomerases I and III is responsible for