Chapter 26, Problem 26.45AP

Interpretation Introduction

Interpretation:

Percentage of C and T that expect in sea urchin DNA has to be predicted.

Concept Introduction:

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. 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 also enhance the stability. Adenine and thymine gives a pair forming two hydrogen bonds and cytosine and guanine gives rise to another pair forming three hydrogen bonds.

Chargaff’s rule: The amount of adenine and thymine were always equal, and the amount of cytosine and guanine are always equal (A=T and G=C). The proportions of each (A/T: G/C) vary from one species to another.