Chapter 23, Problem 82A

Interpretation Introduction

Interpretation:

The relative proportional amounts of A, T, C and G in the given length of DNA should be determined.

Concept introduction:

Nucleic acids are large biomolecules or biopolymers which are essential to different forms of file. Two major types of nucleic acid which are found in living organisms are: DNA and RNA.

Answer to Problem 82A

In the given length of DNA, there are equal amounts of A and T.

In the given length of DNA, there are equal amounts of C and G.

Explanation of Solution

DNA stands for deoxyribonucleic acid which contains five carbon sugar, a nitrogen base and a phosphate group. It stores the biological information or gene information in a sequence of four bases of nucleic acid: Adenine, cytosine, thymine and guanine. DNA has a structure of double helix. It also stores the replicate genetic information.

As it is given that, in the structure of DNA; guanine (G) always linked to cytosine (C) and adenine (A) is always linked to thymine (T). Since, the hydrogen bonds are present between the two strands which hold the bases (pairing) present in DNA molecule with each other in the centre of helix. Thus, C is the complementary pairing base to G whereas T is the complementary pairing base to A.

Hence, the amount of cytosine must be equal to the amount of guanine whereas amount of thymine must be equal to the amount of adenine in the given length of DNA.