Question

Given below are two statements:
Statement I: For effective functioning, the mammalian testes must be maintained at a temperature higher than that of the body
Statement II: Anatomical features of the testes and scrotum permit the regulation of testicular temperature
In the light of the above statements, choose the most appropriate answer from the options given below

• A. Both Statement I and Statement II are true
• B. Both Statement I and Statement II are false
• C. Statement I is correct but Statement II is false
• D. Statement I is incorrect but Statement II is true

Hint:

Testicular Thermoregulation: Testes MUST be $2 - 6^\circ\text{C}$ COOLER than body temperature. Regulated by Pampiniform plexus, Tunica dartos, and Cremaster muscle.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Testicular thermoregulation: optimal mammalian spermatogenesis strictly requires a scrotal temperature $2^\circ - 6^\circ ext{C}$ below core body temperature.
Key Formula or Approach:
\[ \text{Testicular Temperature} = T_{\text{core}} - (2^\circ\text{C to } 6^\circ\text{C}) \quad [\text{Pampiniform Plexus Countercurrent Heat Exchange}] \]

Step 2: Detailed Explanation:
1. Statement I: Mammalian spermatogenesis is heat-sensitive; normal viable sperm production requires the testes to be maintained at $2^\circ$ to $6^\circ ext{C$ LOWER (cooler)} than core body temperature, not higher. Core body temperature causes germ cell degeneration and azoospermia. Hence, Statement I is incorrect.
2. Statement II: The pendulous scrotum, tunica dartos smooth muscle, cremaster muscle, thin sweat-gland rich scrotal skin, and pampiniform venous plexus countercurrent heat exchanger precisely regulate testicular temperature. Hence, Statement II is true.

Step 3: Final Answer:
Thus, Statement I is incorrect but Statement II is true, corresponding to option (D).