Menstrual Cycle

Question 1

What do
1. Theca cells
2. Granulosa cells
3. Luteal cells
produce?

Answer 1

1. Androstenedione
2. Estrogen
3. Estrogen and progesterone (luteal cells are the theca and granulosa cells post ovulation)

Question 2

2 parts of the ovarian (menstrual) cycle

Answer 2

Ovarian component (concerned with maturing an oocyte and its ovulation)
Endometrial component (concerned with creating an environment that nurtures fertilized ovum)

Question 3

What cell types do
1. LH
2. FSH
act on?

Answer 3

1. Theca cells

2. Granulosa cells

Question 4

4 actions of estradiol

Answer 4

Granulosa cell proliferation
Estrogen receptors
FSH receptors
LH receptors on granulosa cells

Question 5

Dominant follicle

Answer 5

First follicle to develop LH receptors on granulosa cell
Responds to LH with estrogen surge
Inhibits sister follicles development

Question 6

Early ovarian follicular phase

Answer 6

Primary follicles respond to increasing FSH levels

Developing theca and granulosa cells

Question 7

Late ovarian follicular phase

Answer 7

Dominant follicle (gets LH receptors)
Responds to LH with estrogen surge
Positive feedback effect on anterior pituitary
Results in LH spike prior to ovulation

Question 8

How is estrogen produced between the theca and granulosa cells?

Answer 8

LH binds to theca cells
Cholesterol is taken into cell and metabolized into androstenedione
Diffuses into granulosa cell
FSH binding to granulosa cell allows it to convert to estrogen using aromatase

Question 9

Ovulatory phase

Answer 9

Surge of LH resulting from estrogens from the dominant follicle is critical for ovulation
LH surge requires 2 days of elevated estrogen

Question 10

3 ways LH triggers ovulation

Answer 10

Neutralized action of oocyte maturation inhibitor
Induces an enzyme (prostaglandin endoperoxidase synthase) to result in prostaglandin, etc production
Degradation and contraction of follicular wall

Question 11

Ovarian luteal phase

Answer 11

Post ovulation
In response to elevated LH, granulosa and theca cells form luteal cells
Luteal cells respond to LH by producing progesterone and estrogen

Question 12

If oocyte is not fertilized, the luteal cells degenerate after how long?

Answer 12

~12 days

Question 13

3 parts of the endometrial cycle

Answer 13

Proliferative
Secretory
Atretic

Question 14

Proliferative endometrial phase

Answer 14

Cells lining the uterus divide in response to estradiol from granulosa cells, forming a layer of glands and blood vessels

Question 15

Secretory endometrial phase

Answer 15

After ovulation, cell division halts

Progesterone augments the blood supply and initiated the secretion of acid mucin

Question 16

Atretic endometrial phase

Answer 16

In the absence of a fertilized oocyte, progesterone decreases resulting in a loss of the uterine lining
Causes bleeding for 2-7 days

Question 17

Progesterone inhibits what 3 hormones

Answer 17

GnRH
FSH
LH