Which phase of the menstrual cycle directly follows ovulation?

Correct Answer: B

Rationale: The correct answer is B: Luteal phase. Following ovulation, the ruptured follicle transforms into the corpus luteum, which secretes progesterone to prepare the uterine lining for potential implantation. This phase typically lasts around 14 days. The other choices are incorrect because: A: Menstrual phase occurs at the beginning of the cycle with shedding of the uterine lining. C: Proliferative phase occurs before ovulation, characterized by the thickening of the uterine lining. D: Follicular phase occurs before ovulation, characterized by the development of ovarian follicles.

Correct Answer: A

Rationale: The correct order of the stages of labor is Dilation, Expulsion, Placental (Choice A). Firstly, dilation refers to the opening of the cervix to allow the baby to pass through. Secondly, expulsion is when the baby is delivered. Lastly, the placental stage involves the delivery of the placenta after the baby is born. This sequence is crucial for a safe delivery and recovery. Choices B, C, and D are incorrect because they do not follow the natural progression of labor stages and may lead to complications if followed.

Correct Answer: A

Rationale: Morning sickness is a common sign of pregnancy caused by hormonal changes. It typically occurs in the first trimester. The other choices are not signs of pregnancy. Luteal phase defect is a menstrual cycle disorder, mature corpus luteum is a normal part of the menstrual cycle, and dysmenorrhea is painful periods. Thus, A is the correct answer as it directly relates to pregnancy.

Correct Answer: C

Rationale: The acrosome in sperm contains enzymes that help it penetrate the egg during fertilization. These enzymes break down the outer layer of the egg, allowing the sperm to enter and fertilize it. This makes choice C the correct answer. Choices A and D are incorrect because the acrosome is not responsible for providing energy for movement or producing enzymes for sperm maturation. Choice B is also incorrect as storing sperm is not the primary role of the acrosome.

Correct Answer: A

Rationale: The correct answer is A: Seminal vesicles. Seminal vesicles are responsible for producing the majority of the fluid in semen, contributing to sperm motility and viability. The other choices are incorrect because: B: Epididymis stores and transports sperm; C: Testes produce sperm; D: Vas deferens transports sperm from the epididymis to the urethra.