Which of the following is not a role of semen?

Correct Answer: C

Rationale: The correct answer is C because semen does not contain enzymes that enhance sperm motility. Sperm motility is primarily influenced by the structure and health of the sperm themselves. Semen aids in sperm transport, provides nutrients, buffers the acidic vaginal environment, and contains antibiotics. Enzymes in semen primarily help with liquefaction of semen after ejaculation, not sperm motility. Choices A, B, and D are incorrect because semen does dilute sperm, neutralizes the acidic vaginal environment, and contains antibiotic chemicals, respectively.

Correct Answer: B

Rationale: The correct answer is B: Day 14. Ovulation typically occurs around day 14 of a female's menstrual cycle. This is because ovulation is triggered by a surge in luteinizing hormone (LH) which usually happens midway through the cycle. Ovulation marks the release of an egg from the ovary, making conception possible. Days 7, 21, and 24 are not typically associated with ovulation as they are either too early or too late in the menstrual cycle for the surge in LH to occur. It is important to note that the timing of ovulation can vary among individuals and cycles, but day 14 is considered the average for a 28-day menstrual cycle.

Correct Answer: D

Rationale: The correct answer is D: orchiditis. Orchiditis refers to inflammation of the testicle, which is a type of tissue found in the male reproductive system. This condition specifically affects the testicular tissue, leading to pain, swelling, and possible complications. Skeletal muscle (choice A) is not related to the testicle, phimosis (choice B) is a condition of the foreskin, and epithelial tissue (choice C) primarily covers the surface of organs, not the testicle itself. Therefore, orchiditis is the most relevant choice for a condition affecting testicular tissue.

Correct Answer: A

Rationale: The correct answer is A. The hormone produced by the corpus luteum that helps maintain pregnancy is progesterone. After ovulation, the ruptured follicle forms the corpus luteum, which secretes progesterone to support the uterine lining for potential implantation. Choice B is incorrect as cleavage refers to early cell divisions in embryo development. Choice C is incorrect as fertilization is the fusion of sperm and egg. Choice D is incorrect as estrogen is primarily produced by the ovaries.

Correct Answer: A

Rationale: The correct answer is A because a spermatid is a mature male germ cell that arises from the process of spermatogenesis, not a secondary sex characteristic. - B is incorrect as a primary spermatocyte is indeed typical of males in the process of spermatogenesis. - C is incorrect as a secondary spermatocyte is an intermediate stage in spermatogenesis. - D is incorrect as deepening voice is a secondary sex characteristic associated with male puberty.