Chapter 25, Problem 3P

(a)

Summary Introduction

To determine: Turns of the double helix that must be unwound during replication of the E.coli chromosome if total base pairs in E.coli are 4,641,652 bp.

Introduction:

Replication model of DNA is semi-conservative where one strand in the next generation has a light band labeling and one strand has a dark band labeling of N-14 and N-15 atoms respectively.

(b)

Summary Introduction

To determine: Time taken to replicate the E.coli chromosome at 37°C, if two replication forks proceeded from origin. It is assumed that replication occurs at a rate of 1000 bp/sec with assumption that E.coli cells divide every 20 min.

Introduction:

Replication forks are formed during the stage of synthesis of DNA. It involves the bi-directional method of replication of DNA with formation of a leading and a lagging strand of DNA.

(c1)

Summary Introduction

To determine: The number of Okazaki fragments formed after replication of E.coli.

Introduction:

Okazaki fragments are small nucleotides segments of DNA which bind to the complementary segments on single stranded DNA lagging strand during the process of DNA synthesis.

(c2)

Summary Introduction

To determine: The factors that determine the numerous Okazaki fragments are assembled in the correct order in the new DNA.

Introduction:

The process of DNA replication synthesis involves the formation of leading and lagging strands. Lagging strand with the addition of the Okazaki fragments synthesizes the new template with the help of enzyme DNA polymerase.