Question

Briefly discuss the structure and functions of DNA.

Answer 1

Structure of DNA: Watson and Crick suggested that DNA is made up of two strands that twist around each other to form a right-handed DNA. The two DNA strands are anti-parallel. The backbone of DNA is made up of sugar and phosphate. There are approximately 10 nitrogenous bases per turn in DNA. It has major grooves and minor grooves. Nitrogenous bases are purine and pyrimidine. Purines are adenine (A) and cytosine (C). Pyrimidines are Thymine (T) and guanine (G). In DNA, there are two hydrogen bonds between adenine (A) and thymine (T) and three hydrogen bonds between cytosine (C) and guanine (G). These are called as complementary base pairs.

Function of DNA: It stores the genetic information. The information is transmitted from parents to children through the process of DNA replication. When DNA is replicated, it makes a duplicate copy of its DNA, then the cell divides, resulting in the correct distribution of one DNA copy to each resulting cell. It is also used as a source of nucleosides and nucleotides.