Exam 1 Flashcards
(139 cards)
Gonadal hormones
Estrogen, progesterone, testosterone
Menstrual cycle is mediated through which structures of the body
Hypothalamus, anterior pituitary gland, ovaries
What gland is responsible for stimulating the anterior pituitary gland to produce gonadotropin
Hypothalamus
What gland is responsible for stimulating the anterior pituitary gland to produce gonadotropin
Hypothalamus
Follicle-stimulating hormone
released by anterior pituitary gland
Function of FSH
stimulates growth and development of the Graafian follicle-which secretes estrogen
What hormone does the Graafian follicle secrete
estrogen
When does the anterior pituitary gland secrete luteinizing hormone (LH) and what does it stimulate?
It secretes LH before ovulation to stimulate the development of the corpus luteum
When does the anterior pituitary gland secrete luteinizing hormone (LH) and what does it stimulate?
It secretes LH after ovulation to stimulate the development of the corpus luteum
What hormone is responsible for maintaining pregnancy
Progesterone
Where is progesterone secreted from
Corpus luteum
What happens to the levels of estrogen and progesterone when pregnancy does not occur
They decline because the corpus luteum degenerates
What happens as a result of decreased levels of estrogen and progesterone
The uterus sheds its lining (period)
What is estrogen responsible for
development of secondary sex characteristics and deposition of fat in the buttocks and mon pubis
What does estrogen help regulate
Menstrual cycle by stimulating proliferation of the endometrial lining in preparation for pregnancy
What is the role of progesterone
Regulates menstrual cycle by decreasing uterine motility and contractility (which is caused by estrogen)
-“prolife” hormone because it helps pregnancy remain viable
-readies breasts for lactation
Where is human chorionic gonadotropin (hCG) produced
trophoblast (outermost layer of developing blastocyte)
What is the function of hCG
maintains corpus luteum by keeping levels of progesterone and estrogen elevated until the placenta takes over
-used to measure pregnancy
Menstrual phase
time of vaginal bleeding
signals beginning of follicular phase of ovarian cycle
What triggers the menstrual phase
Declining levels of estrogen and progesterone->poor endometrial support and constriction of endometrial blood vessels-> decreased O2 and nutrients to endometrium-> lining of uterus sheds
What is the role of prostaglandins
cause contractions of smooth muscle and decrease risk of hemorrhage
When does the proliferative phase begin
End of menses through ovulation (appx. days 7-14)
Characteristics of the proliferative phase
-gradually increasing levels of estrogen
-enlarging endometrial glands
-growth of uterine smooth muscle
When does the secretory phase occur
time of ovulation to period just before menses