Chapter 9, Problem 45A

Summary Introduction

To compare:

The ages of men and women who are diagnosed with cancer.

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. A cell cycle has a system of control checkpoints to monitor the cycle and stop it if something goes wrong. Sometimes cells fail to respond to normal cell cycle control mechanisms and this leads to cancer.

Answer to Problem 45A

Both men and women can suffer from pancreatic cancer. Women are more likely to develop cancer at younger age than men. As per the given data, the frequency of cancer for women peaks at 70 to 75 years of age and for men it peaks at 75 to 80 years of age.

Explanation of Solution

Cancer occurs when the normal cell cycle is disrupted and the cell does not respond to control mechanisms. Cancer is uncontrolled growth and division of cells. These unchecked cancer cells can even kill the organism by crowding out normal cells. The changes occur in regulation of cell growth and division of cancer cells due to mutations or changes in certain segments of DNA. Often the genes are altered due to some environmental factors, age and food habits. As the person ages, more and more changes occur in DNA. With the accumulation of these changes, an aged person might develop cancer.

As per the given graph the women in the age group of 70 to 75 are more prone to developing cancer than men. The critical age for men to develop cancer is 75 to 80 years.