Physio 7

Question 0

follicular phase

Answer 0

FSH stimulates development of follicles. (FSH and rising estradiol)

estradiol promotes proliferation of the endometrium and primes the uterus for progesterone actions

Question 1

ovarian cycle

Answer 1

a series of hormone-mediated changes in the ovaries culminating in the monthly production of a viable ovum in women of reproductive age

Question 2

ovulatory phase

Answer 2

LH surge causes rupture of the Graafian follicle. (LH Surge)

Question 3

luteal phase

Answer 3

LH converts the ruptured follicle to a corpus luteum. (LH, high progesterone and some estradiol) Progesterone converts proliverative uterus to a secretory uterus

Question 4

what happens to corpus luteum if no fertilization occurs?

Answer 4

degenerates and forms a corpus albicans. (low estrogen and progesterone)

Question 5

primordial follicle

Answer 5

increases in size during the ovarian cycle. contains the ovum, thecal, and granulosa cells

Question 6

proliferative phase

Answer 6

11 days. thickness of endometrium increases. dominated by estrogens

Question 7

secretory phase

Answer 7

12 days. dominated by progesterone. promotes accumulation of glycogen, increased glandular secretions, and increased vascularity

Question 8

menstrual phase

Answer 8

associated with prostaglandin-mediated vasoconstriction of spiral arteries and local ischemic injury/inflammation. associated with regression of the corpus luteum (5 days)

Question 9

hormonal regulation of the menstrual cycle

Answer 9

HnRH stimulates release of FSH and LH, and estrogen synth by follicles has negative feedback. In late follicular phase, blood estradiol reaches a high level that initiates positive feedback and a surge in LH and FSH, provoking ovulation. luteal phase shows negative feedback. Estradiol, progesterone, and inhibin produced by corpus luteum have negative feedback on gonadotropin release

Question 10

pulsatile release of GnRH and LH

Answer 10

estrogens in late follicular phase sensitize the anterior pituitary gonadotrophs to stim by GnRH. this produces a mid cycle surge of LH release necessary for the rupture of the growing follicle and ovulation

Question 11

GnRH

Answer 11

secreted by neurons in the arcuate nucleus and preoptic area of hypothal. reaches gonadotrophs in pituitary to increase synth and secretion of FSH and LH

Question 12

regulation of gonadotropin secretion

Answer 12

GnRH binds to a G protein coupled receptor on the gonadotroph membrane. triggers IP3/DAG pathway. causes gonadotrophs to make and release FSH and LH

Question 13

estrogen and progesterone metabolism

Answer 13

derived from cholesterol. steroid hormones. bind to albumin and sex hormone-binding globulins in serum. estrogen inactivated in liver through conjugation, progesterone rapidly degraded in liver to steroids. both excreted in urine.

Question 14

2 cell, 2 gonadotropin model of steroid synth (follicular phase)

Answer 14

during follicular phase, major product of follicle is estradiol. during luteal phase, major product of corpus luteum is progestins. LH primes theca cell to convert cholesterol to androstenedione. Theca cell cant make estradiol due to lack of aromatase. Androstenedione diffuses to granulosa cell where aromatase has been stimulated by FSH. here, estradiol is made.

Question 15

2 cell, 2 gonadotropin model of steroid synth (luteal phase)

Answer 15

corpus luteum makes LDL available to granulosa-lutein cells. theca-lutein and granulosa-lutein cells can both make progesterone. for production of 17-a-OH progesterone, some of the progesterone diffuses into the theca-lutein cell which has the hydroxylase needed for conversion of progesterone

Question 16

estrogen effects

Answer 16

proliferation of uterine endometrial stroma and development of endometrial glands. prolif and development of mucosal lining of fallopian tubes. stim of bone growth through osteoclast inhibition. increased fat deposition in subcutaneous tissue. during follicular phase, induce endometrial gene products that promote growth and prime the uterus for progesterone through inducing progesterone receptors

Question 17

progesterone effects

Answer 17

secretory changes in the uterine endometrium. decreased freq and intensity of uterine contractions. increased fallopian tube secretions. during luteal phase, induces genes that convert uterus to a secretory type.

Question 18

puberty and the phases

Answer 18

the transition to cyclic female reproductive function. thelarche: breast development. Adrenarche: increased secretion of adrenal androgens. Menarche: menstrual cycles begin. estrogen promotes rapid bone growth, deposotion of fat, and ductile growth in boobs. progesterone promotes development of lobules and aveoli in boobs

Question 19

negative feedback before puberty

Answer 19

release of gonadotropins is low before puberty due to the low amounts of sex steroids. negative feedback sensitivity is high. GnRH eventually begins to pulse at night then during the day

Question 20

menopause

Answer 20

cyclic reproductive function and menstruation cease. usually 51-52 years old. no remaining ovarian follicles, which causes decrease in steroid hormones level of circulating sex steroids decrease. circulating gonadotropins increase due to lack of estrogen (loss of negative feedback) a variety of physical and mental changes occur

Question 21

estrone

Answer 21

made by muscle and adipose tissue. provides a postmenopausal source of estrogen. no where near as potent as estradiol.

Question 22

why are women at risk for osteoporosis and fractures after menopause?

Answer 22

estrogens prevent bone loss. a healthy diet of vitamin D and calcium is needed to preserve bone mass, as well as weight bearing exercise