Which phase of the menstrual cycle is characterized by the shedding of the uterine lining?

Correct Answer: C

Rationale: Rationale: 1. The menstrual phase is the phase where the uterine lining sheds. 2. This occurs when there is no pregnancy and the hormone levels drop. 3. Shedding of the lining leads to menstrual bleeding. 4. The follicular phase is characterized by follicle development. 5. The luteal phase follows ovulation and prepares the uterus for a potential pregnancy. 6. Ovulation refers to the release of the egg from the ovary, not shedding of the uterine lining. Summary: - A: Follicular phase - Incorrect, focuses on follicle development. - B: Luteal phase - Incorrect, prepares the uterus for potential pregnancy. - C: Menstrual phase - Correct, characterized by shedding of uterine lining. - D: Ovulation phase - Incorrect, refers to the release of the egg.

Correct Answer: C

Rationale: The correct answer is C: Epididymis. The epididymis is a coiled tube located on top of the testes where sperm are stored after production. It allows for maturation and storage of sperm before they are ejaculated. The other choices, A: Seminal vesicle, B: Vas deferens, and D: Prostate gland, do not store sperm. The seminal vesicle produces seminal fluid, the vas deferens transports sperm from the testes to the urethra, and the prostate gland secretes fluid that nourishes and protects sperm. Therefore, the epididymis is the correct choice as it specifically stores sperm after production.

Correct Answer: A

Rationale: Estrogen is the correct answer because it increases the permeability of the cervix to sperm during ovulation. Estrogen is responsible for the changes in cervical mucus consistency, making it easier for sperm to swim through to reach the egg. Progesterone, FSH, and LH do not directly affect cervical mucus permeability during ovulation. Progesterone prepares the uterine lining for implantation, FSH stimulates follicle growth, and LH triggers ovulation.

Correct Answer: A

Rationale: Step 1: Oxytocin is known as the "love hormone" and plays a crucial role in uterine contractions. Step 2: During labor, oxytocin is released to stimulate rhythmic contractions of the uterus. Step 3: These contractions help to push the baby through the birth canal. Step 4: Therefore, the primary purpose of oxytocin during labor is to stimulate uterine contractions for the progression of labor. Summary: Choice A is correct because oxytocin's main function during labor is to stimulate uterine contractions. Choices B, C, and D are incorrect as oxytocin does not inhibit contractions, increase progesterone production, or directly prepare the cervix for dilation during labor.

Correct Answer: A

Rationale: The correct answer is A: Testosterone. Testosterone is the primary male sex hormone responsible for the development of secondary sexual characteristics such as facial hair, deepening of the voice, and muscle growth. It is produced by the testes in males. Estrogen (B) and Progesterone (C) are female sex hormones, while LH (D) is luteinizing hormone that stimulates the production of testosterone in males but is not responsible for the development of secondary sexual characteristics.