Lecture 39 Unit 5

Question 1

where are the hormones located that control the female cycle

Answer 1

hypothalamus, anterior pituitary, and ovary

Question 2

what are the two female cycles

Answer 2

ovarian cycle and uterine cycle

Question 3

what is the ovarian cycle

Answer 3

changes in the ovary during and after maturation of the oocyte

Question 4

what is the uterine cycle

Answer 4

preparation of the uterus to receive fertilized ovum and if implantation does not occur the stratum functionalis is shed off

Question 5

what happens in the ovary in the menstrual phase

Answer 5

• about 20 follicles that began to develop 6 days before are now secreting estrogen
• fluid is filling the antrum of gransulosa cells

Question 6

what is happening in the uterus in the menstrual phase

Answer 6

• declining levels of progesterone causes spiral arteries to constrict and glandular tissue degnerates
• stratum functionalis layer if sloughed off with 50 to 150 mL of blood

Question 7

what happens in the ovary in follicular phase in the preovulatory phase

Answer 7

• follicular secretion of estrogen snd inhibit has slowed the secretion of FSH
• dominant follicle emerges by day 6
• by day 14, Graafian follicle has enlarged and bulges at surface
• increasing estrogen levels trigger the secretion of LH

Question 8

what happens in the uterus in proliferative in the preovulatroy phase

Answer 8

increasing estrogen levels have repaired and sickened the stratum functionalis to 4-10 mm in thickness

Question 9

what happens in preovulatory phase in moderate concentrations of estrogen

Answer 9

estrogen inhibits the release of GnRH

Question 10

what happens in preovulatory phase in high concentrations of estrogen

Answer 10

estrogen stimulates release of GnRH

Question 11

what are the steps in ovulation

Answer 11

1. high level of estrogens from almost mature follicle stimulate release of more GnRH and LH
2. GnRH promotes release of FSH and LH
3. LH surge brings about ovulation

Question 12

what happens in the ovary in luteal phase of the postovulatroy phase

Answer 12

• if fertilization does not occur, corpus albicans is formed
• if fertilization occurs, developing embryo secretes hCG which maintains health of corpus luteum and its hormonal secretions

Question 13

what happens in the uterus in the secretory phase of the postovulatroy phase

Answer 13

• hormones from corpus luteum promote thickening of endometrium
• if no fertilization occurs, menstrual phase will begin

Question 14

how is the female repro cycle regulated by hormones

Answer 14

• GnRH secreted by hypothalamus controls the female repro cycle by stimulating anterior pituitary to secrete FSH and LH
• FSH initiates growth of follicle that secrete estrogen
• LH stimulates ovulation and promotes formation of the corpus luteum which secretes estrogens, progesterone, relaxing and inhibin

Question 15

what does progesterone do

Answer 15

prepares uterus fro implantation and the mammary glands for milk secretion

Question 16

what does relaxin do

Answer 16

facilitated implantation in the relaxed uterus

Question 17

what does inhibin do

Answer 17

inhibits secretion sof FSH

Question 18

what does estrogen do

Answer 18

maintains reproductive organs

Question 19

at low concentrations of estrogen what happenes

Answer 19

estrogen stimulates release of GnRH

Question 20

what happens in the follicular phase

Answer 20

• FSH stimulates development of astral follicles
• antral follicles secrete estradiol
• around day 6 one astral follicle becomes dominant and the rest undergo atresia
• estradiol peak precede LH surge

Question 21

what happens in ovulatory phase

Answer 21

Lh surge stimulates ovulation of mature follicle within 24-36 hours

Question 22

what happens in luteal phase

Answer 22

• corpus luteum forms
• corpus luteum secretes progesterone and estradiol
• luteolysis begins about day 25 in non pregnant women

Question 23

what happens in menstrual phase

Answer 23

discharge of endometrial tissue and blood

Question 24

what happens in proliferative phase

Answer 24

estradiol stimulates growth of endometrium

Question 25

what happens in secretory phase

Answer 25

• nutrients capable of sustaining embryo

- decline of progesterone and estradiol at end of secretory phase permit release of prostaglandins

Question 26

when is LH secretion highest? lowest?

Answer 26

highest-menopause

lowest-childhood

Question 27

what is the function of the placenta

Answer 27

site of nutrient, gas, and waste exchange

Question 28

what is the placenta not a barrier to

Answer 28

drugs and alcohol