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Human Reproduction — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Reproduction1 Mark
Question
For two statements are given-one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both assertion and reason are true, and reason is the correct explanation of assertion.
  2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
  3. Assertion is true, but reason is false.
  4. Both assertion and reason are false.
Assertion: A drop in temperature does not affect spermatogenesis.
Reason: During temperature drop, the smooth muscles contracts and bring the testes closer to the pelvic cavity.
✓

Answer

  1. Both assertion and reason are true, and reason is the correct explanation of assertion.

​​​​​​​​​​​​​​​​​​​​​Explanation:

The normal temperature of the testes in the scrotum is about 2º-2.5ºC lower than the internal body temperature. When the body is chilled, the smooth muscle contracts and brings the testes closer to the pelvic cavity. This movement towards the pelvic cavity allows the testes to absorb heat from the rest of the body so that the sperm cells do not become chilled and get optimum temperature for spermatogenesis.

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