Chapter 4, Problem 1A

Summary Introduction

Introduction:

The level of organization includes the cells, tissues, organ and organ system. The tissues are formed by the growth and differentiation of cells, organ are formed by the differentiation of the tissue cells, organ system comprises of lungs, heart, brain, stomach, pancreas, spleen, intestine, liver and kidney.

Answer to Problem 1A

Correct answer:

In the level of the organization of the living, the tissues are formed by the growth and division of the cells by the process of mitosis. The organs are formed by the differentiation and organization of the tissue cells. Therefore, option (b) is correct.

Explanation of Solution

Reason for the correct statement:

The level of organization leads to the formation of tissues from the cells by the process of division in the body. The tissue formed includes the connective tissue, nervous tissue, epithelial tissue, and muscular tissue. The organs are formed by the growth and differentiation of the tissues in the body of the living organisms like human beings.

Option (b) is given as “cells; organs”.

“Tissues are formed from cells and are arranged together to form organs”, it is the right answer.

Hence, option (b) is correct.

Reasons for the incorrect statements:

Option (a) is given as “organs; organ systems”.
Tissues are formed from cells and not organs and organs are formed from tissues. Organ systems are formed from organs and not tissues. So, it is a wrong answer.

Option (c) is given as “cells; molecules”.
The tissues are arranged to form organs, not the molecules. So, it is a wrong answer.

Option (d) is given as “molecules; cells”.
The tissues are formed from cells and not molecules. The tissues arrange to form the organs, not the cells. So, it is a wrong answer.

Hence, options (a), (c) and (d) are incorrect.

Conclusion

The tissues are formed by the growth and division of the cells and the tissues are arranged to form the organs in the level of organization of life.