The structures of the vulva lie ____________ to the vagina.

Correct Answer: B

Rationale: The correct answer is 'Inferior.' The structures of the vulva are positioned below the vagina, making them inferior. Choice A, 'Posterior,' refers to structures located at the back, not below the vagina. Choice C, 'Lateral,' means to the side, which is not the correct orientation in this context. Choice D, 'Superior,' indicates above, which is the opposite of the correct relationship described in the question.

Correct Answer: B

Rationale: The regenerative phase of the menstrual cycle is the phase in which the endometrium rebuilds after menstruation. This phase can vary in duration from woman to woman and cycle to cycle. Choice A, the ovulatory phase, is not variable as it typically lasts around 24 hours. Choice C, the secretory phase, is also relatively consistent in its duration. Choice D, the menstrual phase, is the shedding of the endometrial lining and usually lasts around 3-7 days.

Correct Answer: A

Rationale: Luteinizing hormone is responsible for maintaining the corpus luteum after ovulation. This is crucial for the production of progesterone, which helps prepare the endometrium for implantation and supports early pregnancy. Choices B, C, and D are incorrect: B is the function of follicle-stimulating hormone (FSH) which stimulates the growth of ovarian follicles, C is mainly regulated by prolactin, and D is primarily associated with estrogen and progesterone.

Correct Answer: C

Rationale: A morula is a stage in embryonic development where a solid ball of 12-16 cells is formed after several rounds of mitotic division following fertilization. The zygote is the initial cell formed by the fusion of sperm and egg. Blastomere refers to individual cells in a developing embryo. A blastocyst is a later stage where a fluid-filled cavity forms within the embryo. Therefore, the correct answer is 'Morula.'

Correct Answer: A

Rationale: A cord inserted to the very edge of the placenta is known as battledore insertion. This occurs when the cord is attached to the fetal membranes at the placental margin rather than directly to the placental tissue. Placenta velamentosa refers to the condition where the umbilical cord inserts into the fetal membranes before it reaches the placenta. Placenta accreta is a condition where the placenta attaches too deeply into the uterine wall. Vasa Praevia is a condition where fetal blood vessels run across or near the internal cervical opening.