Contraceptive pills containing estradiol or estradiol plus progesterone are given at programmed doses during the ovarian cycle to prevent follicle maturation and ovulation. Explain how these pills work.
What will be an ideal response?
Slightly elevated levels of estradiol or estradiol and progesterone inhibit both GnRH at the hypothalamus and the
release of FSH and LH from the pituitary. Without FSH, primordial follicles do not initiate development, and the endogenous levels of estrogen remain low. An LH surge is necessary for ovulation to occur, and the LH surge is
triggered by the peaking of estradiol. If the level of estradiol is not allowed to rise above the critical level, the LH surge will not occur and ovulation will not occur, even if a follicle managed to develop to a stage at which it could ovulate. Any mature follicles would ultimately degenerate, and no new follicles would mature to take their place. Although the ovarian cycle is interrupted, the level of hormones is still adequate to regulate a normal menstrual cycle.
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Fill in the blank(s) with correct word
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Indicate whether the statement is true or false.
This area houses the body's "internal thermostat"
a. hypothalamus. b. cerebellum. c. skin. d. cerebral cortex. e. medulla.
All of the muscles listed, except one, are innervated by the deep fibular nerve. Select the exception
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