ANIMAL REPRODUCTION QUESTION 1979: L. PETERSON/AP BIOLOGY Describe the role of the hypothalamus, the pituitary hormones, and the ovarian hormones in the regulation of the human menstrual cycle. Include in your discussion the concept of feedback control and the way in which fertilization of the egg alters the menstrual cycle.
STANDARDS: Hypothalamus and Feedback: Maximum 6 pts. __low progesterone or estrogen resulting in positive feedback __secretion of a releasing factor __secretion of pituitary FSH __high level of progesterone or estrogen resulting in negative feedback __causing a decrease in LH releasing factor __causing a decrease in LH __the "pill" and its influence on feedback __influence of stress on feedback Pituitary Hormones: Maximum 6 pts. __FSH secretion by the pituitary gland __the effect of FSH on egg formation __stimulation of estrogen secretion by FSH __LH (or FSH & LH) resulting in ovulation __corpus luteum formation by LH stimulation __progesterone secretion by LH stimulation __decreased LH causing corpus luteum breakdown __formation of corpus albicans Ovarian Hormones: Maximum 4 pts. __estrogen secretion by follicles inhibiting menstrual flow __estrogen secretion initiating endometrial growth __progesterone from corpus luteum promoting further endometrial growth & vascularization __low level of progesterone and estrogen causing menstrual flow Fertilization: Maximum 2 pts. __effect of human or placental chorionic gonadotropin on the pituitary gland __no menstrual cycle Bonus Point: Maximum 1 pt. __mentioning the days or phases of the cycle __a good descriptive diagram __a high estrogen level resulting in stimulation of the hypothalamus to release more LHRF Maximum of 12 if Fertilization and Feedback are not included in the discussion. Maximum of 14 if either Fertilization or Feedback are discussed and not both.