Menstruation

Question 1

What are the two processes that make up the menstrual cycle?

Answer 1

the development of the egg and the development of the endometrium

Question 2

What coordinates the two processes?

Answer 2

Hormones

Question 3

What is the goal of the cycle?

Answer 3

To develop an egg and to prepare for pregnancy

Question 4

What are the three cycles?

Answer 4

Ovarian, Endometrial and Hormonal

Question 5

What does menarche mean?

Answer 5

The first period a girl gets

Question 6

When does the development of an egg starts?

Answer 6

During the fetal stage when a branch of stem cells will specialise and become primary oocytes.

Question 7

How many chromosomes do primary oocytes have?

Answer 7

46

Question 8

What process do the primary oocytes have to go through to become a mature egg?

Answer 8

The double division of meiosis

Question 9

How long will the double division take?

Answer 9

years

Question 10

What will the primary oocyte do before finishing the first division?

Answer 10

It will freeze. At birth a baby girl is born with all of her potential eggs frozen in this state. They will remain like this for years?

Question 11

What happens at the menarche?

Answer 11

The hypothalamus will start releasing GnRh that will start the menstrual cycle, making the first division continue and complete, generating a secondary oocyte.

Question 12

When is the egg finally mature?

Answer 12

At the point of fertilisation. The mature egg is also called the ovum

Question 13

What is the process of maturation?

Answer 13

It is what happens to a single cell inside the ovary. This small cell develops inside a ball of cells called a follicle

Question 14

What part is released during ovulation?

Answer 14

The inside while the follicle will remain in the ovary

Question 15

How long does the maturation of the follicle take?

Answer 15

Around 3 months

Question 16

How many follicles start the maturation process?

Answer 16

Several but only one will fully develop into a mature egg in response to hormonal changes

Question 17

What happens in the first stage of the ovarian cycle?

Answer 17

Activated by the hypothalamus, the pituitary gland starts the cycle by releasing a hormone called FSH. This stimulates the follicle to grow.

Question 18

What is the second stage of ovulation?

Answer 18

Once the follicles have developed enough they start producing more and more oestrogen which signals they are ready for ovulation. FSH is no longer needed and the levels start to fall.

Question 19

What happens 12 hours after the peak of oestrogen?

ovulation cycle

Answer 19

The pituitary gland sends the order of ovulation by releasing a big peak of LH.

Question 20

What happens after 24 hours?

ovulation cycle

Answer 20

Ovulation will happen and the levels of LH will fall. The oocyte will start its travel through the uterine tube, while the follicle will remain in the ovary, maintaining oestrogen to stimulate the growth of the endometrium to prepare for implantation.

Question 21

What is stage 5 of the ovulation cycle?

Answer 21

It is now transformed into the corpus luteum. This corpus luteum starts producing progesterone to maintain the endometrium and protect the fertilised egg until it’s able to produce its own hormones in the primitive placenta.

Question 22

What happens if there is not pregnancy?

Answer 22

The corpus luteum will degenerate in corpus albicums (white body), and the levels of oestrogen and progesterone will fall, finishing the cycle and signalling the pituitary gland to start the next cycle again with FSH.

Question 23

What happens during mensturation?

Answer 23

The levels of oestrogen and progesterone have fallen which leads to menstrual bleeding.

Question 24

What happens in the proliferative phase?

Answer 24

When the endometrium grows. The endometrium remains at its basal level until the oestrogen level starts to grow again with the follicle development.

Question 25

What happens if there is a pregnancy?

endometrium cycle

Answer 25

The corpus luteum continues developing, progesterone levels are maintained and develop the endometrium further to nourish and develop the future placenta. the blastocyte releases human chorionic gonadotrophic (hcG) which stimulates the continuation of progesterone production.

Question 26

What happens if there is no pregnancy?

Answer 26

reducing the levels of oestrogen and progesterone stimulate prostaglandin which causes the spiral arteries of the endometrium to go into spasm to restrict blood flow and the endometrium dies.