Question

In which of the following would you expect to find the most highly conserved sequences of nucleic acids?

• A. Structurally critical regions of a polypeptide such as an active site region
• B. The intron regions of pre-mRNA sequences
• C. Ribosomal RNA sequences
• D. Bacterial genes conferring antibiotic resistance

Answer 1

The correct option is A Structurally critical regions of a polypeptide such as an active site region

Introns are nucleotide sequences that are removed during maturation of the RNA. Exons are the actual encoding nucleotide sequences present in the mature RNA. Structurally critical regions of a polypeptide such as active site region are highly conserved sequences of nucleic acids. These are highly conserved because mutation in these regions will result in formation of defective protein. For example, if active site region is not highly conserved, mutation will result in production of nonfunctional active site.

Thus, the correct answer is 'Structurally critical regions of a polypeptide such as an active site region.'