Question

(a) State how the constant internal environment is beneficial to organisms.
(b) Explain any two alternatives by which organisms can overcome stressful external conditions.

Answer 1

Hint: With the aid of a self-regulatory process, the living organism often continues to stay in a constant state. Such a condition is referred to as homeostasis, which requires the maintenance of a constant internal environment.

Complete answer:
First let’s explain the benefits of organisms towards a constant internal environment.
(a) Organisms benefit from a constant internal environment by enabling organisms for both biochemical processes and physiological activities to continue with maximum efficiency, thus improving the overall efficiency of the organism i.e., increase of overall fitness of the organism.
- Despite changing external environmental factors that threaten to upset their homeostasis, species should strive to preserve the constancy of their internal environment, i.e. homeostasis.
- By using artificial means such as heaters and air conditioners, human beings can preserve their homeostasis.

(b) The two alternatives by which species are able to withstand stressful external environments are follows-
- Migration-organisms travel temporarily under challenging circumstances to a favorable environment and return after the time is over.
- Aestivation and Hibernation are forms during summers and winters to escape stress.

Note: A constant internal environment cannot be sustained by nearly 99 percent of animals and virtually all plants. Their body temperature varies with the temperature of the environment.