Chapter 10, Problem 6CONQ

Summary Introduction

To review:

The results of an experiment which involves taking two pieces of string of a given length, forming a deoxyribonucleic acid (DNA) coil, creating supercoils by fixing one end of the coil, and observing the following:

A. Change in the number of turns by introducing three more turns.

B. Handedness of the coil.

C. Formation of supercoils, if any, on introducing three turns.

D. Degree of similarity between real DNA and the model after adding rubber cement and allowing it to harden.

Introduction:

Supercoiling is a method used for packaging DNA inside the cell nucleus (in eukaryotes) or into a nucleoid (in bacteria). It involves twisting the DNA coil on itself. Depending on the direction in which the coil is twisted, the supercoil can be positive or negative.