Question

what is the role of telomerase in dna replication? it links together the base pairs. it adds telomeres to the ends of the dna strands to prevent the loss of genetic information. it proofreads and corrects the newly replicated dna.

Explanation:

To determine the role of telomerase in DNA replication, we analyze each option:

• The first option ("It links together the base pairs") is incorrect. Base pairing is facilitated by hydrogen bonds, and DNA polymerase (not telomerase) is involved in linking nucleotides during replication.
• The second option ("It adds telomeres to the ends of the DNA strands to prevent the loss of genetic information") is correct. Telomerase is an enzyme that synthesizes telomeric DNA sequences (telomeres) at the ends of chromosomes. During DNA replication, the lagging strand synthesis cannot fully replicate the very end of the chromosome, leading to the shortening of telomeres over time. Telomerase adds repetitive nucleotide sequences (telomeres) to the 3' end of the DNA strand, which helps prevent the loss of essential genetic information from the chromosome ends.
• The third option ("It proofreads and corrects the newly replicated DNA") is incorrect. Proofreading and correction of newly replicated DNA are primarily the functions of DNA polymerase (which has a proofreading exonuclease activity) and other mismatch repair enzymes, not telomerase.

Answer:

The correct option is: It adds telomeres to the ends of the DNA strands to prevent the loss of genetic information.