Chapter 26.6, Problem 26.13P

Interpretation Introduction

Interpretation:

Difference between DNA ligase and DNA polymerase has to be accounted.

Concept Introduction:

Composition of nucleic acid: Nucleic acid is a polymer of nucleotides. Each nucleotide has three parts: a sugar, a nitrogenous base, and a phosphate group. Two nucleotides are joined by phosphate diester linkage where a free phosphate on 5’ carbon of one nucleotide and a free –OH group on 3’ carbon of another nucleotide is linked.

Base pairing in DNA: The two strands of the DNA double helix run in the opposite directions: one in 5’ to 3’ direction and other from 3’ to 5’ direction (complementary strand). The hydrogen bonding between two strands enhances the stability of the DNA; where the alignment of hydrophobic nitrogenous bases in the interior and hydrophilic phosphate and sugar groups on the exterior, is present that enhance the stability too. Adenine and thymine gives a pair forming two hydrogen bonds and cytosine and guanine gives rise to another pair forming three hydrogen bonds.

Replication of DNA: The process by which copies of DNA are made when a cell divides.