Question

In mammals, the testes occur in scrotal sacs outside the viscera because of the

• A. Presence of urinary bladder
• B. Presence of rectum
• C. Long vas deferens
• D. Requirement of low temperature for spermatogenesis

Answer 1

The correct option is D Requirement of low temperature for spermatogenesis

In mammals, the testes occur in scrotal sacs outside the viscera because of the requirement of low temperature for spermatogenesis. The testes are situated outside the abdominal cavity within a pouch called scrotum. The scrotum helps in maintaining the low temperature of the testes (2–2.5${}^o$ C lower than the normal internal body temperature), which is necessary for spermatogenesis. The slightly cooler temperature of the scrotum is necessary for the development of normal sperm. So, the testes start their development in the abdominal cavity and descend into the scrotal sacs during the 7${}^{th}$ month of the fetal life, in presence of testosterone hormone.

Thus, the correct answer is 'Requirement of low temperature for spermatogenesis'.