The Menstrual Cycle

Question 1

What is the menstrual cycle?

Answer 1

The menstrual cycle is a series of events that occurs every 28 days on average in the female if fertilisation has not taken place

Question 2

When does the menstrual cycle begin?

Answer 2

It begins at puberty

Question 3

When does the menstrual cycle end?

Answer 3

It continues until the menopause

Question 4

What is the menopause?

Answer 4

The menopause is when ovulation and menstruation stop happening in a female

Question 5

Between what ages does the menopause usually occur?

Answer 5

Usually between the ages of 45 and 55

Question 6

The events of a typical menstrual cycle can be summarised under what headings?
(4)

Answer 6

Days 1-5

Days 6-14

Day 14

Day 14-28

Question 7

What occurs between days 1-5 of the menstrual cycle?

4

Answer 7

The old lining of the uterus/the endometrium breaks down and is shed from the body

The loss of blood and tissue through the vagina is called the menstruation

Meiosis occurs in an ovary to produce a new egg

The new egg is surrounded by the Graafian follicle

Question 8

Between days 1-5, what breaks down and is shed from the body?

Answer 8

The old lining of the uterus is shed

Question 9

What is called menstruation?

Answer 9

The loss of blood and tissue (the old lining of the uterus) through the vagina

Question 10

What is produced between days 1 and five?

Answer 10

A new egg is produced

Question 11

What happens to the newly produced egg between days 1 and 5?

Answer 11

It is surrounded by the Graafian follicle

Question 12

What occurs between days 6-14 of the menstrual cycle?

2

Answer 12

The developing Graafian follicle produces oestrogen which causes the endometrium to thicken again

Oestrogen prevents new eggs from developing so normally only one Graafian follicle develops during each menstrual cycle

Question 13

What produces oestrogen between days 6-14?

Answer 13

The developing Graafian follicle produces oestrogen

Question 14

What causes the endometrium to thicken between days 6-14?

Answer 14

Oestrogen produced by the developing Graafian follicle

Question 15

What does oestrogen prevent from happening between days 6-14?

Answer 15

Oestrogen prevents new eggs from developing

Question 16

What prevents new eggs from developing between days 6-14?

Answer 16

Oestrogen

Question 17

What occurs at day 14?

4

Answer 17

Ovulation occurs when the Graafian follicle burst to release the egg from the ovary

The egg passes into the abdomen of the female and on into the funnel of the Fallopian tube

The egg is then moved along the Fallopian tube

The egg is normally only available for fertilisation for up to 48 hours after ovulation

Question 18

For how long is the egg available for fertilisation after ovulation?

Answer 18

48 hours

Question 19

When does ovulation occur on day 14?

Answer 19

It occurs when the Graafian follicle burst to release the egg from the ovary

Question 20

What happens after ovulation on day 14?

Answer 20

The egg passes into the abdomen of the female and on into the funnel of the Fallopian tube

Question 21

What happens to the egg after it has passed into the funnel of the Fallopian tube on day 14?

Answer 21

It is moved along the Fallopian tube

Question 22

What occurs between days 14 and 28 of the menstrual cycle?

9

Answer 22

The remains of the Graafian follicle develop into the corpus luteum (yellow body)

The corpus luteum makes the hormone progesterone (and some oestrogen) which causes the endometrium to thicken even more

Progesterone prevents new eggs from forming

The egg that was released will die by day 16 if it is not fertilised

If fertilisation has not taken place the corpus luteum starts to degenerate around day 22

This results in a reduction in progesterone levels, which causes the lining of the uterus to break down on day 28

On day 28 the spongy, nutritive lining of the uterus breaks down and is released from the body through the vagina

This bleeding is called menstruation

The onset of bleeding marks the start of a new monthly menstrual cycle

Question 23

What develops into the corpus luteum between days 14 and 28?

Answer 23

The remains of the Graafian follicle develops into the corpus luteum (yellow body)

Question 24

What is produced by the corpus luteum between days 14 and 28?

Answer 24

The corpus luteum makes the hormone progesterone

Question 25

What does progesterone produced by the corpus luteum do between days 14 and 28?
(2)

Answer 25

It causes the endometrium to thicken even more

It prevents new eggs from forming

Question 26

Before what day will the egg die if it is not fertilised?

Answer 26

It will die before day 16 if not fertilised

Question 27

When will the corpus luteum start to degenerate if fertilisation does not take place?

Answer 27

It will begin to degenerate around day 22 if fertilisation does not take place

Question 28

What does the degeneration of the corpus luteum around day 22 result in?

Answer 28

This results in a reduction in progesterone levels which cases the lining of the uterus to break down on day 28

Question 29

What occurs on day 28?

Answer 29

The spongy, nutritive lining of the uterus breaks down and is released from the body through the vagina (menstruation)

Question 30

What does the onset of bleeding mark?

Answer 30

The onset of bleeding marks the start of a new monthly menstrual cycle

Question 31

Define menstruation

Answer 31

Menstruation is the discharge of the lining of the uterus (endometrium) and the unfertilised egg