Question

DNA polymerases ___________ Group of answer choices

A) break hydrogen bonds between complementary nucleotides to unwind/unzip the double helix.
B) seal gaps between DNA fragments.
C) synthesize new stretches of DNA during DNA replication.
D) proofread DNA molecules.

Answer 1

DNA polymerases synthesize new stretches of DNA during DNA replication (Option C) by adding nucleotides to the template strand and proofreading the new strand for errors. They are essential for the copying of DNA in cell division.

Step-by-step explanation:

DNA polymerases have a specific role in the process of DNA replication. The correct answer to the question regarding the function of DNA polymerases is C) synthesize new stretches of DNA during DNA replication. This is because DNA polymerases recognize each base in a template strand and match it to the complementary base in a free nucleotide, catalyzing the formation of the phosphodiester bond between nucleotides to extend the new strand. They also possess proofreading abilities to ensure high fidelity during DNA synthesis. Other enzymes like DNA helicase and topoisomerase are involved in unwinding the DNA and relieving tension ahead of the replication fork, while DNA ligase seals gaps between DNA fragments. However, the synthesis of new DNA strands is accomplished by DNA polymerase.

Answer 2

Answer: C

Explanation: The DNA Polymerase is an enzyme that adds one nucleotide at a time to the -OH free 3' end of a forming DNA strand. These nucleotides match to the ones from another DNA strand, which is used as a model. As soon as the complementary chain has been made, another DNA polymerase will repeat the process on it, to make its matching strand, which should be the same as the first one used as a model. Two DNA work on each of the two DNA separated strands, to make a copy of the other one.