AP BIOLOGY

Detailed explanation-1: -which strand grows continuously towards the replication fork? DNA polymerase III builds new strands from scratch during DNA replication.

Detailed explanation-2: -The main function of the third polymerase, Pol III, is duplication of the chromosomal DNA, while other DNA polymerases are involved mostly in DNA repair and translesion DNA synthesis. Together with a DNA helicase and a primase, Pol III HE participates in the replicative apparatus that acts at the replication fork.

Detailed explanation-3: -Answer and Explanation: The answer to the question would be, option b. It can synthesize DNA in 5’ to 3’ direction.

Detailed explanation-4: -Polymerase does not create a novel DNA strand from scratch. Instead it synthesizes a new strand of DNA based on the template of two existing DNA strands. It does this with the help of another enzyme, called helicase, which unwinds the double helix structure of the DNA molecule into two single DNA strands.

Detailed explanation-5: -After the primer is in place on a single, unwound polynucleotide strand, DNA polymerase wraps itself around that strand, and it attaches new nucleotides to the exposed nitrogenous bases. In this way, the polymerase assembles a new DNA strand on top of the existing one (Figure 3).