Question

Homeostasis is a condition where the organisms:

• A. Maintain a constant internal environment in an ever-changing external environment
• B. Do not maintain a constant internal environment
• C. Change their internal environment according to their external environment
• D. Change their internal environment when the external environment is constant

Hint:

Homeostasis is essential for survival in dynamic environments.

Answer 1

The Correct Option is A

Homeostasis is a fundamental biological process where organisms maintain a stable internal environment despite changes in external conditions.

(A) Correct: Homeostasis involves maintaining a constant internal environment (e.g., body temperature, pH, glucose levels) even when the external environment changes.

(B) Incorrect: This contradicts the definition of homeostasis.

(C) Incorrect: Organisms regulate their internal environment to remain stable, not to mirror external changes.

(D) Incorrect: Homeostasis is about stability during external fluctuations, not changing internally when the external environment is constant.

The correct answer is (A), as it describes the core principle of homeostasis.

Answer 2

Homeostasis refers to the ability of an organism to maintain a stable internal environment despite fluctuations in the external environment. For example:

• Body temperature regulation : Humans maintain a core body temperature of ~37°C even in extreme heat or cold.
• Blood glucose levels : Insulin and glucagon regulate sugar levels regardless of food intake.
• pH balance : Blood pH is tightly controlled between 7.35 and 7.45.

This stability is crucial for proper cellular function and survival. Organisms do not allow their internal conditions to fluctuate based on external changes.

• (A): Correct because it accurately defines homeostasis as maintaining a constant internal environment despite external variability.
• (B): Incorrect because organisms actively work to maintain stability.
• (C): Incorrect because changing internal conditions would disrupt homeostasis.
• (D): Incorrect because homeostasis ensures stability regardless of external constancy.