The Menstrual Cycle Flashcards Preview

The Endocrine System > The Menstrual Cycle > Flashcards

Flashcards in The Menstrual Cycle Deck (22)
Loading flashcards...
1

What is the term given to describe the inception of menstruation around puberty?

Menarche

2

What triggers the menarche?

Increasing GnRH levels

3

What comprises an ovarian follicle?

An oocyte surrounded by granulosa and theca cells

4

What is the function of theca cells?

Produce androgens

5

What is the function of granulosa cells?

Conversion of androgens (using aromatase) to oestrogens

6

What are the two key phases of the menstrual cycle?

  1. Follicular phase
  2. Luteal phase

7

Which days does the follicular phase typically occupy within the menstrual cycle?

Days 1 - 12

8

The follicular phase begins with __________

The follicular phase begins with menstruation

9

Which hormone begins to rise first in the follicular phase and what is its impact?

Gonadotrophin releasing hormone (GnRH)

Increases secretion of FSH and LH from the anterior pituitary

10

Which hormone acts on theca cells and what is the outcome?

LH

Androgen production

11

Which hormone cats on granulosa cells and what is the outcome?

FSH

Oestrogen production

12

___________ levels rise throughout the follicular phase

Oestrogen levels rise throughout the follicular phase

13

____ causes maturation of follicles until a _________ (dominant) follicle emerges

FSH causes maturation of follicles until a Graafian (dominant) follicle emerges

14

Between which days does a surge in LH occur and what does it cause?

12-14

Ovulation

15

High levels of oestrogen have what impact on which hormone?

Inhibition of FSH

16

What happens to the remaining follicle after ovulation?

It becomes the corpus luteum and secretes progesterone (and some oestrogens)

17

What effect does progesterone have?

  1. Increases thickness and secretory activity of endometrium
  2. Increases basal body temperature
  3. Increases cervical mucus thickness
  4. Aids glandular development in the breasts

18

What effect do high progesterone levels have on which two other hormones?

Inhibition of FSH and LH

19

What happens when there is failure of fertilisation?

  1. Degeneration of the corpus luteum
  2. Fall in progesterone levels
  3. Fall in oestrogen levels
  4. Vasospasm of of arterioles supplying endometrium
  5. Necrosis of endometrium and menstruation

20

A fall in progesterone levels has which effect on which two other hormones?

Rise in FSH and LH

(inhibitory effect removed)

21

What is the most potent oestrogen produced and what does it cause?

Oestradiol

  1. Secondary sexual charcateristics
  2. Contributes to bone and CV health

22

Which hormone stimulates the transformation of the empty follicle to the corpus luteum?

LH