Molecular Biology and Genetics MCQs

Determine the correctness or otherwise of the following Assertion (A) and the Reason (R). Assertion: The association constant in water for the G-C base pair is three times lower than that for the A-T base pair. Reason: There are three hydrogen bonds in the G-C base pair and two in the A-T base pair.

5' capping of mRNA transcripts in eukaryotes involves, the following events: P. Addition of GMP on the 5' end. Q. Removal of γ-phosphate of the triphosphate on first base at the 5' end. R. 5' - 5' linkage between GMP and the first base at 5' end. S. Addition of methyl group to N7 position of guanine. Which one of the following is the correct sequence of events?

Determine the correctness of the following statements. I. Enhancer sequences are those DNA sequences that are involved in increasing the rate of DNA replication. II. Enhancer sequences work by binding with eukaryotic gene activator factors.

Based on their function, find the odd one out

For their efficient translation, eubacterial mRNAs possess a Shine-Dalgarno sequence for its recognition by an anti-Shine-Dalgarno sequence (ASD) in the ribosomes. The correct statement is

In transgenics, alterations in the sequence of nucleotide in genes are due to P. Substitution Q. Deletion R. Insertion S. Rearrangement

Peptidyl transferase activity resides in

A DNA sequence, 5'-ATGGACGTGCTTCCCAAAG-CATCGGGC-3', is mutated to obtain P. 5'- ATGGACGTGCTTCaCAAAGCATCGGGC -3' Q. 5'- ATGGACGTGCTTCCCgAAAGCATCGGGC -3' R. 5'- ATGGACGTGCTTCC-AAAGCATCGGGC -3' S. 5'- ATGGACGTGCTTCCCAAtGCATCGGGC -3' T. 5'- ATGGACGaGCTTCCCAAAGCATCGGGC -3' [Point mutations are shown in the lower case or '-' within the sequences] Which of the above mutant sequences do not have frameshift?

DNA helicases catalyze the reaction