Chapter 25, Problem 1SQ

Which of the following statements concerning homeostasis is not true?

1. a. It is the maintenance of constant internal conditions.
2. b. It involves the regulation of body conditions, such as glucose level.
3. c. It usually prevents major fluctuations in body conditions.
4. d. Its maintenance is solely the responsibility of the endocrine system.

Summary Introduction

Concept introduction: Homeostasis is the maintenance of the body condition where internal environment is maintained in a constant state even if there is a significant change in the external environment. The body has several mechanisms to maintain the homeostasis. The endocrine system is part of the homeostasis control system to keep the molecules produced under check. Only when the products of the endocrine system that is the hormones are produced, several other molecules can be produced.

Answer to Problem 1SQ

Correct answer: Homeostasis is maintained by several control systems, which includes the hypothalamus, the endocrine system, excretory system, circulatory system, and many more. Endocrine system alone is not responsible for maintaining homeostasis. Therefore option d. is correct.

Explanation of Solution

Reasons for correct statement:

Homeostasis is the maintenance of an internal balance. The animal body is made up of several organs that should perform their function in unison. Every organ system contributes in some way to maintain the homeostasis. Endocrine system is also involved in maintaining the homeostasis, but it is not the only system that is responsible for homeostasis. The hypothalamus is the master regulator of homeostasis by controlling all other organs involved in homeostasis.

Option d. is given as “Its maintenance is solely the responsibility of the endocrine system”

As endocrine system is not the only organ system that is responsible for homeostasis and several other organs system are involved, option d. is a false statement. Hence,option d. is the correct answer.

Reasons for the incorrect statements:

Option a. is given as “It is the maintenance of constant internal conditions”.

Homeostasis is present in the body systems in order to maintain constant conditions of all systems and thereby make all the systems work in unison. Option a. is a true statement. So, option a. in incorrect.

Option b. is given as “It involves in the regulation of body functions, such as glucose level”.

All the cells of the organ systems must produce molecules in the threshold level. One such molecule is the glucose. Glucose must be produced within the threshold level. If the glucose levels exceed the threshold level, the feedback mechanisms get activated to bring down the glucose level. Thus, homeostasis regulates glucose level, which is part of the normal body function. Option b. is a true statement. So, option b. is incorrect.

Option c. is given as “It usually prevents major fluctuations in body conditions”.

Homeostasis is responsible for maintaining the body conditions in a steady state. Homeostasis mechanism thus should prevent any changes in the internal environment. Option c. is a true statement. So, option c. is incorrect.

Hence, options a., b., and c. are incorrect.

Conclusion

Homeostasis is the maintenance of the internal environment and is maintained by several organ systems.