Which hormone is responsible for stimulating milk production after childbirth?

Correct Answer: A

Rationale: The correct answer is A: Prolactin. Prolactin is the hormone responsible for stimulating milk production after childbirth. It is produced by the pituitary gland and plays a key role in lactation. Oxytocin, another hormone, is responsible for milk ejection during breastfeeding, not milk production. Estrogen and progesterone are involved in regulating the menstrual cycle and pregnancy, not milk production. Therefore, the correct choice is A as it directly relates to milk production post-childbirth.

Correct Answer: A

Rationale: Estrogen is the correct answer because it is responsible for thickening the cervical mucus during ovulation. Estrogen levels increase during the follicular phase of the menstrual cycle, leading to the production of thick, clear mucus that helps sperm travel to the egg for fertilization. Progesterone, FSH, and LH do not directly influence cervical mucus consistency during ovulation.

Correct Answer: C

Rationale: The correct answer is C, the Fallopian tube. Fertilization typically occurs in the ampulla of the Fallopian tube, where the egg and sperm meet. This site provides the ideal environment for fertilization due to the presence of cilia that help move the egg and sperm towards each other. Additionally, the Fallopian tube provides nourishment and support for the developing embryo before it travels to the uterus for implantation. The other choices are incorrect because: A: The ovary is the site where eggs are produced but not where fertilization occurs. B: The cervix is the lower part of the uterus and serves as a passageway for sperm to enter the uterus but not the site of fertilization. D: The uterus is where the fertilized egg implants and develops into a fetus, but fertilization itself does not occur in the uterus.

Correct Answer: C

Rationale: Estrogen is the correct answer as it plays a key role in regulating the menstrual cycle by stimulating the growth of the uterine lining. It also triggers ovulation and helps maintain the pregnancy if fertilization occurs. FSH and LH are involved in the release of eggs and development of follicles but are not primarily responsible for regulating the entire menstrual cycle. Progesterone is important for preparing the uterus for potential pregnancy but is not the primary regulator of the menstrual cycle.

Correct Answer: C

Rationale: The correct answer is C: Estrogen. Estrogen is responsible for the growth and development of mammary glands in females during puberty and pregnancy. It stimulates the proliferation of glandular tissue, leading to the enlargement and maturation of the mammary glands. Prolactin (choice A) stimulates milk production, oxytocin (choice B) triggers milk ejection, and progesterone (choice D) prepares the breast tissue for lactation but does not directly cause growth and development of mammary glands.