Question

Consider the following statements Statement I: Cyclical seasonal morphological variations in certain organisms is called cyclomorphosis. Statement II: Allen's rule states that with the increase of every $10^{\circ}C$ the rate of metabolic activities double in organisms. The correct answer is

• A. Both statements I and II are true
• B. Both statements I and II are false
• C. statement I is true, but statement II is false
• D. statement I is false, but statement II is true

Hint:

Allen's Rule: Endotherms in cold climates have shorter extremities to minimize surface area and heat loss. Endotherms in warm climates have longer extremities.

Answer 1

The Correct Option is C

Concept: This tests two ecological and physiological principles.
Explanation: Statement I is **True**: **Cyclomorphosis** is the phenomenon of cyclic changes in body form in response to seasonal environmental changes, common in zooplankton. Statement II is **False**: The principle that a $10^{\circ}\text{C}$ temperature increase doubles the metabolic rate is the $\mathbf{Q_{10}}$ **effect** (or Van't Hoff's rule). **Allen's rule** relates to the size of extremities (limbs, ears) in endotherms in relation to climate.