With respect to Sertoli cells which of the following statements is incorrect

Correct Answer: D

Rationale: The correct answer is D because Sertoli cells do secrete inhibin, but it does not inhibit luteinizing hormone secretion. Inhibin actually inhibits follicle-stimulating hormone (FSH) secretion. Sertoli cells support spermatogenesis by nourishing developing sperm (A), they are stimulated by testosterone (B), and they also phagocytose defective sperm (C). Therefore, option D is incorrect as it misrepresents the role of inhibin in the endocrine regulation of the male reproductive system.

Correct Answer: B

Rationale: The correct answer is B: ovaries. Ovaries are the organs responsible for producing, storing, and releasing human eggs. They are oval-shaped and play a crucial role in the female reproductive system. The other choices are incorrect because: A: clitoris is a small, sensitive organ located near the entrance of the vagina, not involved in egg production. C: Fallopian tubes are responsible for transporting eggs from the ovaries to the uterus, not for producing or storing eggs. D: Vagina is the muscular tube connecting the uterus to the outside of the body, not involved in egg production.

Correct Answer: C

Rationale: Rationale for correct answer (C): The main function of the testicles is spermatogenesis, which is the process of producing sperm cells. This is a crucial role in male reproductive system. Spermatogenesis occurs in the seminiferous tubules of the testes. Other functions like producing androgenic hormones (choice B) are mainly carried out by the Leydig cells in the testes, not the testicles themselves. While the testicles do play a role in semen production (choice D), this is not their primary function. Therefore, the correct answer is C as it directly relates to the main purpose of the testicles in the male reproductive system.

Correct Answer: C

Rationale: Step-by-step rationale for Choice C (Continues the epididymal duct) being the correct answer: 1. The deferent duct, also known as the vas deferens, is a continuation of the epididymal duct. 2. Sperm mature and are stored in the epididymis before passing into the vas deferens. 3. The vas deferens carries sperm from the epididymis to the ejaculatory duct during ejaculation. Summary: - Choice A is incorrect because the deferent duct does not join with the seminal vesicle duct to form the ejaculatory duct. - Choice B is incorrect as the vas deferens does not continue the rete testis. - Choice D is incorrect as the vas deferens is an intratesticular spermatic duct, not extratesticular.

Correct Answer: A

Rationale: The correct answer is A: head. The spermatozoon is composed of three main parts: head, mid piece or neck, and flagellum. The head contains the nucleus which carries genetic material. The mid piece or neck contains mitochondria for energy production. The flagellum is responsible for sperm motility. In this question, the head is the most essential part of the spermatozoon as it contains the genetic material required for fertilization. The other choices (B: mid piece or neck, C: flagellum, D: body) are incorrect as they are important for sperm function but do not carry the genetic material necessary for fertilization.