Choose the CORRECT statement regarding events that occur in metaphase II.

Correct Answer: A

Rationale: Correct Answer: A - Sister chromatids may no longer be identical to each other. Rationale: 1. In metaphase II, sister chromatids align at the metaphase plate. 2. During meiosis II, sister chromatids separate and move to opposite poles. 3. Due to potential crossing over in meiosis I, sister chromatids may not be identical in meiosis II. 4. This variability contributes to genetic diversity in the resulting gametes. Summary: B: Homologous chromosomes do not line up in metaphase II; they already separated in meiosis I. C: Crossing over occurs in meiosis I, not in meiosis II. D: Homologous chromosomes start to separate in anaphase I, not metaphase II.

Correct Answer: B

Rationale: The correct answer is B, slight chills and fever. This finding may indicate an infection, which can be a serious complication post-endometrial biopsy. Fever and chills can be signs of systemic infection, requiring immediate medical attention to prevent further complications. Mild cramping (A) is a common post-procedure symptom. Spotting of blood (C) is also normal after an endometrial biopsy. Fatigue (D) after anesthesia is expected and not an immediate concern unless severe or persistent.

Correct Answer: C

Rationale: The correct answer is C: spermatogonia. At the age of five, boys have not reached puberty yet, so they do not produce sperm cells. Spermatogonia are the precursor cells that give rise to sperm cells later in puberty. Spermatocytes are the cells that undergo meiosis to form sperm cells, spermatozoa are mature sperm cells, and spermatids are the immediate precursors to sperm cells. Therefore, the only cells present in a male age five would be spermatogonia, as they are the early-stage cells in the process of spermatogenesis.

Correct Answer: D

Rationale: The correct answer is D: GnRH. Gonadotropin-releasing hormone (GnRH) is released from the hypothalamus, stimulating the pituitary gland to produce FSH and LH, which then trigger the changes of puberty. FSH and LH are not the initial hormones that start puberty, but rather the result of GnRH stimulation. Testosterone and ICSH are also involved in puberty but are not the primary hormone that initiates the process.

Correct Answer: A

Rationale: The correct answer is A: uterine tube. During ovulation, the mature oocyte is released from the ovary and travels through the uterine tube (fallopian tube) towards the uterus for potential fertilization. The uterine tube is the pathway for the oocyte to reach the uterus. Choices B, C, and D are incorrect because the oocyte does not directly pass into the uterus, pelvic cavity, or ovary during ovulation.