How many autosomes does a human primary spermatocyte have?

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: 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.

Correct Answer: C

Rationale: The correct answer is C: Puberty. Puberty is the stage of development when gametes are produced and secondary sex characteristics appear, marking the beginning of the fertile period. This period typically occurs between the ages of 10 to 14 in females and 12 to 16 in males. A: Teenage - Incorrect. Teenage refers to the age range between 13 to 19 and does not specifically indicate the onset of gamete production and secondary sex characteristics. B: Adolescence - Incorrect. Adolescence is a broader term that encompasses the period from childhood to adulthood, including puberty, but it does not specifically indicate the beginning of the fertile period. D: Juvenile - Incorrect. Juvenile refers to a young organism that has not reached sexual maturity and does not signify the beginning of gamete production and secondary sex characteristics.

Correct Answer: C

Rationale: The correct answer is C: Perimetrium. The perimetrium is the outermost layer of the uterus and consists of a thin serous layer of connective tissue. This layer provides support and protection to the uterus. Rationale: 1. Peritoneum (A) is the serous membrane that lines the abdominal cavity, not the outermost layer of the uterus. 2. Pericardium (B) is the membranous sac that surrounds the heart, not related to the uterus. 3. Pericyte (D) is a type of cell found in blood vessels and involved in vascular function, not a layer of the uterus. In summary, the perimetrium is the correct answer as it is the specific layer that forms the outer covering of the uterus, providing structural support and protection.