Menstrual cycles

Question 1

Initiation of pregnancy for the sperm

Answer 1

Sperm must move from the vagina through the uterus and into the fallopian tube. Egg and sperm have to meet within 6-24 hours after ovulation

Question 2

how long after ovulation do the sperm have to meet an egg>?

Answer 2

6-24 hours

Question 3

What must happen to the sperm that allows them to penetrate the zona pellucida surrounding the egg?

Answer 3

capacitation

Question 4

Where does fertilization occur?

Answer 4

upper oviduct

Question 5

survivability (fertilizability) of the ovum?

Answer 5

6-12 hours

Question 6

survivability of the sperm?

Answer 6

1-2 days

Question 7

Sexual interest in women peaks when?

Answer 7

Midcycle (right around the time of ovulation) and just before menstruation

Question 8

volume of ejaculation

Answer 8

1-3 ml, 100 million sperm in each ml

Question 9

Cervical mucus thinning occurs mid cycle and is stimulated by

Answer 9

estrogen

Question 10

motility of the female tract

Answer 10

Prostaglandins in semen, estradiol, oxytocin

Question 11

Highest chance of pregnancy

Answer 11

The day of ovulation or 1-2 days prior. Up to five days prior since thats how long the sperm can survive. Pregnancy chances decrease to zero by one day after ovulation since the egg is only fertilizable for about 6-12 hours

Question 12

At birth, 1 million germ cells

Answer 12

at puberty, 300,000

Question 13

When does menopause start

Answer 13

when all eggs are gone…estrogen falls, FSH and LH rise

Question 14

Cycle

Answer 14

Follicle secretes mainly estrogen (increasing amounts for the first two weeks).
- The estrogen is made by the granulosa cells which make it out of the androgens produced by the thecal cells stimulated by LH The granulosa cells are stimulated by FSH

Question 15

How many follicles develop in each cycle?

Answer 15

only one, this dominany follicle secretes substances that cause the others to regress

Question 16

What makes inhibin and what does inhibin do?

Answer 16

Granulosa cells, it turns off FSH after the follicular phase is over and throughout the luteal phase

Question 17

Cycle starts when

Answer 17

first day of bleeding….period is the start of a cycle not the end

Question 18

Basal body temp rises when

Answer 18

directy after ovulation

Question 19

FSH rises at the end of a cycle and through the period. Why

Answer 19

Because Estrogen, Progesterone, and Inhibin have fallen to allow FSH to rise and begin to stimulate growth of new follicle

Question 20

Estrogen rises throughout the follicular phase why?

Answer 20

When it reaches a certain point it stops being an inhibitory hormone and causes a spike in FSH and LH

Question 21

midcycle LH surge leads to

Answer 21

ovulation

Question 22

BC pills prevent

Answer 22

MIDCYCLE LH SURGE

Question 23

Rise in progesteron around midcycle tells you:

Answer 23

Follicle is changing to corpus luteum

Question 24

Why does Basal body temperature go up?

Answer 24

Progesterone resets the temperature control

Question 25

Endometrial phases during menstrual cycle

Answer 25

- Menstrual phase (5 days)- sloughing off of uterine lining - Proliferative Phase (11 days)- glands that are lined by secretory cells which secrete things like glucose into the uterine lumen to keep the blastocyst viable - Secretory phase- persists through teh luminal phase

Question 26

What provides blood to the proliferative phase and secretory phase uterine linings

Answer 26

spiral arteries

Question 27

During the Follicular phase: Hypothalamus secretes

Answer 27

GnRH

Question 28

GnRH tells the gonadotrophs to secrete what?

Answer 28

FSH and LH

Question 29

FSH stimulates what in the ovary?

Answer 29

Granulosa cells

Question 30

Granulosa cells mak what

Answer 30

Estrogen (from the androgens produced by thecal cells) and Inhibin

Question 31

LH stimulates what

Answer 31

Thecal cells

Question 32

Thecal cells produce what

Answer 32

Androgen which is used to make estrogen

Question 33

Inhibin feeds back where

Answer 33

Anterior pituitary and hypothalamus to decrease LH and FSH

Question 34

KNOW CHART IN NOTES

Answer 34

ok

Question 35

FSH does what to Granulosa cells

Answer 35

causes them to proliferate and produce Estradiol

Question 36

Estradiol stimulates more proliferation in granulosa cells

Answer 36

This is positive feedback

Question 37

Ovulation is triggered by

Answer 37

midcycle LH surge

Question 38

During ovulation, the follicular membrane

Answer 38

ruptures after being attacked by proteolytic enzymes

Question 39

Variation in length of a woman's menstrual cycle is caused by

Answer 39

length of the follicular phase, ie, time for dollicle to develop and the ovum be released

Question 40

hCG

Answer 40

keeps the corpus luteum from degenerating

Question 41

Luteal phase highlight

Answer 41

The development of corpus luteum

Question 42

Corpus luteum begins to develop when

Answer 42

a few days before ovulation (see this by spike in progesterone)

Question 43

How long does the CL last

Answer 43

2 weeks but it is degenerating in the last 5 days. This is called luteolysis

Question 44

CL secretes

Answer 44

estrogen, lots of progesterone, 17 hydroxyprogesterone and inhibin

Question 45

17 hydroxy does what>

Answer 45

who cares