2 Menstrual Cycle Flashcards
What always marks day 1 of the menstrual cycle?
-1st day of menses (bleeding)
Which part of the phase varies in length?
- the FOLLICULAR phase
- may take different times to grow
The follicular phase is characterized by what hormone?
-estrogen
What does estrogen do during the follicular phase?
-Promotes endometrial growth
How can the day of ovulation be determined?
-14 days before the first day of menses! (always)
What phase of the cycle is ALWAYS 2 weeks?
-the Luteal Phase
What hormone characterizes the Luteal Phase?
-Progesterone
What action does Progesterone have on the endometrial lining?
- MAINTAIN UTERINE ENDOMETRIUM
- Thickens mucus from glands (prevents more sperm)
- Increases body temp and hunger
Ovulation occurs chiefly due to a surge in ________ levels.
LH
__________ cells have the exact same enzymatic machinery as the zona reticulata of the adrenal gland.
Theca cells
Theca cells have many __________ receptors that work through _____________
- LH receptors
- work thru cAMP, pkA
Describe the function of pkA in Theca cells.
it activates steps necessary to convert cholesterol into Pregnenolone, to produce ANDROGENS
__________ cells have the same enzymatic machinery as the adrenal zona reticulata PLUS AROMATASE enzyme.
-Granulosa cells
Granulosa cells are always loaded with _________ receptors that work through __________
- FSH receptors
- cAMP, pkA
Estrogen serves as a negative feedback for what 2 pituitary hormones?
- FSH (major)
- LH (minor)
What purpose does Estrogen’s inhibitory effect on FSH serve?
-We only want ONE developing follicle (into one baby)
During the majority of the follicular phase, estrogen serves as ____________ feedback for FSH and LH.
-negative
Describe the effects of Estrogen during the Follicular Phase on the secretory aspects of the endometrium
- causes THIN secretions
- better for sperm to get in
Just prior to menses, what happens to the relationship between Estrogen and FSH/LH?
- Estrogen becomes POSITIVE feedback just prior to menses
- result: hi FSH/LH cause hi Estrogen, and vice versa
Name the only 2 examples of positive feedback?
- Ovulation
- giving birth
The LH surge causes hi amounts of _______ receptor, which causes the follicle to become a ________.
- LH-R
- Corpus Luteum
The Corpus Luteum produces what?
-Progesterone mainly, some Estradiol
hence, this characterizes the luteal phase
The drop in ______________ causes the Endometrial lining to be sloughed off @ menses.
-progesterone
Recall, ____________ cells are on the periphery of the follicle, and they secrete ____________
Theca cells
secrete ANDROGENS
Granulosa cells are derived from ________. Once the secondary oocyte is ejected, the granulosa cells do what?
from follicular cells
use their AROMATASE to make ESTROGENS
