EVERYDAY SCIENCE

Detailed explanation-1: -The problem is solved with the help of an enzyme called primase. Primase makes an RNA primer, or short stretch of nucleic acid complementary to the template, that provides a 3’ end for DNA polymerase to work on. A typical primer is about five to ten nucleotides long.

Detailed explanation-2: -Elongation. During elongation, an enzyme called DNA polymerase adds DNA nucleotides to the 3′ end of the newly synthesized polynucleotide strand.

Detailed explanation-3: -DNA polymerase alpha is almost exclusively required for the initiation of DNA replication and the priming of Okazaki fragments during elongation.

Detailed explanation-4: -DNA polymerase enzymes cannot begin a new polynucleotide chain by linking two nucleoside triphosphates together. Instead, they absolutely require a base-paired 3′-OH end of a primer strand on which to add further nucleotides (see Figure 5-4).

Detailed explanation-5: -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.