What structure corresponds to the scrotum in the male?

Correct Answer: A

Rationale: The correct answer is A: labia major. The scrotum in males corresponds to the labia major in females as they both serve as protective structures for the reproductive organs. The labia major in females is analogous to the scrotum in males in terms of function and location. The other choices are incorrect because the labia minor (B) is a smaller structure located inside the labia major, the pudendal cleft (C) refers to the space between the labia major and labia minor, and the mons pubis (D) is a rounded, fatty area located over the pubic bone.

Correct Answer: B

Rationale: The correct answer is B (44 autosomes) because a human primary spermatocyte is a diploid cell containing a total of 44 autosomes. This is because humans have 22 pairs of autosomes in their somatic cells. During meiosis I, the primary spermatocyte undergoes replication and recombination, resulting in 22 pairs of autosomes (44 autosomes) that will be divided into two haploid secondary spermatocytes. Choices A, C, and D are incorrect because they do not reflect the correct number of autosomes present in a human primary spermatocyte.

Correct Answer: B

Rationale: The correct answer is B (50-100) because each lobule in the testis contains multiple seminiferous tubules where sperm production occurs. The average number of seminiferous tubules per lobule ranges from 50 to 100. This is supported by anatomical studies and research on testicular structure. Explanation: A: 1-3 - This is too low as each lobule contains more seminiferous tubules for efficient sperm production. C: 200-300 - This is too high as it overestimates the number of seminiferous tubules per lobule. D: 500 or more - This is excessive and not accurate based on scientific findings. In summary, choice B is correct because it accurately reflects the typical range of seminiferous tubules per lobule, while the other choices either underestimate or overestimate this number.

Correct Answer: B

Rationale: The correct answer is B: Cervix. The cervix is the lower part of the uterus that opens into the vagina. It acts as a barrier between the uterus and vagina, and allows for the passage of menstrual flow, sperm, and a baby during childbirth. The other choices are incorrect because the urethra is a tube that connects the bladder to the outside of the body, the uterine tubes are also known as fallopian tubes that connect the ovaries to the uterus, and the inguinal canal is a passage in the abdominal wall.

Correct Answer: A

Rationale: The correct answer is A: first menses. Menarche refers to the onset of a girl's first menstrual period, signifying the beginning of her reproductive years. This event marks the maturation of the reproductive system and the ability to conceive. The other choices are incorrect because menarche does not refer to the permanent cessation of menses (choice B), the first sign of sperm production (choice C), or the time of first ovulation (choice D). Menarche specifically pertains to the first menstrual cycle in females, indicating the initiation of their menstrual and reproductive functions.