Chapter 9, Problem 19A

Summary Introduction

Introduction:

Cells reproduce by a cycle of growing and dividing called the cell cycle. Prokaryotic cells reproduce by a method called binary fission. The sequence of events in the life of a eukaryotic cell is called the cell cycle. It includes cellular growth and cell division. There are three main stages of a cell cycle; interphase, mitosis and cytokinesis.

Answer to Problem 19A

Correct answer :

The correct answer is option D. 64

Explanation of Solution

Explanation/justification for the correct answer:

Option D. 64- The second stage in a cell cycle is mitosis in which cell’s nucleus and nuclear material divides. In this stage, the cell’s replicated genetic material separates and the cell prepares to split into two cells. Mitosis results in two daughter cells that are genetically identical. Each mitotic division results in doubling of cells.

After 1^st division there will be 2 new cells. Now if these 2 new cells underwent mitosis they would produce (2x2) 4 new cells. From 4 cells we would get 8 (2x4) new cells. After 4^th division there would be 16 cells. Similarly after 5^th division there would be 32 new cells.

After six divisions of mitosis, there would be 64 new cells formed. Hence this is the correct option.

Explanation for incorrect answer:

Option A. 13- Mitosis results in two daughter cells that are genetically identical. Each mitotic division results in doubling of cells. After six divisions of mitosis, there would be 64 new cells formed.Hence this option is incorrect.

Option B. 32- Mitosis results in two daughter cells that are genetically identical. Each mitotic division results in doubling of cells. After six divisions of mitosis, there would be 64 new cells formed.Hence this option is incorrect.

Option C. 48- Mitosis results in two daughter cells that are genetically identical. Each mitotic division results in doubling of cells. After six divisions of mitosis, there would be 64 new cells formed.Hence this option is incorrect.