Menstrual Cycle

Question 1

What are eggs contained in within the ovaries?

Answer 1

Follicles

Question 2

How long does the follicular phase of the ovarian menstrual cycle last?

Answer 2

Day 1-13

Question 3

What does a follicle consist of?

Answer 3

One primary oocyte surrounded by granulosa cells.

Question 4

What do granulosa cells secrete?

Answer 4

Oestrogen, progesterone and inhibin

Question 5

Give the stages of development of a primordial follicle.

Answer 5

1. Primary follicle
2. Preantral follicle
3. Early antral follicle
4. Mature follicle

Question 6

How do primary follicles receive nutrients?

Answer 6

Cytoplasmic processes on granulosa cells pass nutrients & chemical messengers via gap junctions

Question 7

How does the primary follicle grow into the preantral follicle?

Answer 7

By mitosis of the granulosa cells

Question 8

What does the connective tissue surrounding the granulosa cells differentiate into?

Answer 8

Theca cells

Question 9

What do theca cells do?

Answer 9

Synthesise oestrogen with the granulosa cells

Question 10

What is an antrum?

Answer 10

Fluid filled space in the early antral follicle.

Question 11

Before early antral follicles develop into mature follicles, they are selected for on the basis of being dominant or not. What happens to the non-dominant follicles?

Answer 11

They undergo atresia - an example of apoptosis.

Question 12

On what basis are dominant follicles selected for?

Answer 12

Oestrogen production

Question 13

What triggers a primary oocyte to emerge from meiotic arrest?

Answer 13

A surge in LH. Occurs at time for ovulation.

Question 14

What is another name for a mature follicle?

Answer 14

Graafian follicle

Question 15

What is ovulation?

Answer 15

When the secondary oocyte is carried out of the ovary and onto the ovarian surface

Question 16

When does ovulation occur?

Answer 16

Day 14

Question 17

How long does the Luteal phase of the ovarian menstrual cycle last?

Answer 17

Day 14-28

Question 18

What forms once the mature follicle discharges its antral fluid and egg?

Answer 18

Corpus luteum (formed of granulosa cells)

Question 19

What does the corpus luteum secrete?

Answer 19

Oestrogen
Progesterone
Inhibin

Question 20

What happens to the corpus luteum if the discharged egg is not fertilised?

Answer 20

Undegoes apoptosis

Question 21

What triggers menstruation and the beginning of a new ovarian menstrual cycle?

Answer 21

Loss of the corpus luteum

Question 22

During the follicular phase, which cells synthesise oestrogen?

Answer 22

Granulosa cells

Question 23

After ovulation, which cells synthesise oestrogen?

Answer 23

Corpus luteum

Question 24

Before ovulation, which cells synthesise progesterone?

Answer 24

Granulosa and theca cells

Question 25

After ovulation, which cells synthesise progesterone?

Answer 25

Corpus luteum

Question 26

How do FSH levels change over the ovarian menstrual cycle?

Answer 26

Increases in early follicular phase Peaks mid cycle Decreased steadily throughout remainder of cycle

Question 27

List the effects of FSH.

Answer 27

1. Aids development of follicle after preantral stage 2. Stimulates granulosa cells to multiply and produce oestrogen 3. Induce LH receptors to form on the granulosa cells

Question 28

Why do FSH levels increase at the end of the ovarian cycle?

Answer 28

There are decreased levels of progesterone, oestrogen & inhibin - removes negative feedback from hypothalamus

Question 29

Which hormone mainly inhibits the secretion of FSH?

Answer 29

Inhibin

Question 30

How do LH levels change over the ovarian menstrual cycle?

Answer 30

Constant for most of the follicular phase Very large mid cycle increase Rapid decrease after ovulation Slow decline during luteal phase

Question 31

List the effects of LH.

Answer 31

1. Stimulates theca cells to proliferate and synthesise androgens (converted to oestrogen in granulosa cells) 2. Induces ovulation 3. Stimulates reactions that transform the granulosa & theca cells into a corpus luteum

Question 32

How do oestrogen levels change over the ovarian menstrual cycle?

Answer 32

``` Remains low and stable in first week Increases rapidly in second week Decreases before LH peaks Second increase via corpus luteum Ends with rapid decrease ```

Question 33

How do progesterone levels change over the ovarian menstrual cycle?

Answer 33

Very low levels during follicular phase After ovulation, large levels due to corpus luteum Rapidly decrease during last days

Question 34

How do inhibin levels change over the ovarian menstrual cycle?

Answer 34

Increases during late follicular phase Remains high during luteal phase Decreases as corpus luteum degenerates

Question 35

What is the epithelia lining the uterus called?

Answer 35

Endometrium

Question 36

What occurs during day 1 of the uterine menstrual cycle (menstrual phase)?

Answer 36

Endometrium degenerates, results in menstrual flow

Question 37

What occurs during the proliferative phase of the uterine menstrual cycle (day 5-10)?

Answer 37

1. Menstrual flow ceases 2. Endometrium thickens and regenerates due to oestrogen 3. Receptors for progesterone are synthesised in endometrial cells

Question 38

What is the smooth muscle layer underlying the endometrium called?

Answer 38

Myometrium

Question 39

Which ovarian phase coincides with the the menstrual and proliferative phases?

Answer 39

Follicular phase

Question 40

What occurs in the secretory phase of the uterine menstrual cycle?

Answer 40

1. Endometrium secretes glycogen 2. Progesterone stimulates the endometrium to be an actively secreting tissue Both processes make the endometrium a hospitable environment for implantation

Question 41

Which ovarian phase coincides with the secretory phase?

Answer 41

Luteal phase

Question 42

What effects do oestrogen and progesterone have on cervical mucus?

Answer 42

Oestrogen: Abundant, clear watery mucus - AT ovulation Progesterone: Thick and sticky antibacterial mucus plug - AFTER ovulation

Question 43

What is menopause?

Answer 43

The cessation of menstruation. Occurs between age 48-52. Ovaries stop releasing eggs.

Question 44

What are the short term symptoms of menopause?

Answer 44

Hot flushes, sweats, headaches, irritability, lethargy, depression, dry skin, shorter menstrual cycle

Question 45

What are the long term symptoms of menopause?

Answer 45

Vaginal dryness, decrease in libido (sexual desire), hair loss, general aches and pains

Question 46

Is LH a peptide or steroid hormone?

Answer 46

Peptide