Chapter 9, Problem 11STP

Summary Introduction

To explain:

Why calling interphase the “resting phase of cell cycle” inaccurate.

Introduction:

A cell grows until it reaches its size limit, then it either stops growing or divides. Most cells undergo division. Cell division helps a cell to reproduce and makes the organism grow and heal certain injuries. Cells reproduce by a cycle of growing and dividing called the cell cycle. There are three main stages of a cell cycle; interphase, mitosis and cytokinesis.

Answer to Problem 11STP

Interphase is the first and longest stage in cell cycle. It is not a resting stage as the cell is very active in this stage. The cell grows, performs all cellular activities and undergoes DNA replication. It prepares itself for the next stage of the cell cycle. Hence it would be inaccurate to call interphase the “resting phase of cell cycle”.

Explanation of Solution

A cell spends most of the time in interphase. It is the stage in which a cell grows, develops into a mature, functioning cell, duplicates its DNA and prepares for nuclear division. It makes copies of DNA to enter the next stage of the cycle. During interphase a cell does not divide but prepares itself for cell division. There are three sub- stages in interphase; G₁, S and G₂. In G₁ stage, cell grows, carries out regular cell functions and prepares for synthesis of DNA. In S stage, DNA is replicated and in G₂ stage cell prepares for cell division. So, many activities take place in interphase. So, the cell is not resting in this stage.