Reproduction: trigger 1

Question 1

how does contraception work

Answer 1

by maintaining high levels of progesterone , which inhibits the release of FSH and LH–> meaning no ovulation

Question 2

why can you take contraception orally

Answer 2

because hormonal steroid–> therefore won’t be digested

Question 3

hcG is produced by

Answer 3

trophoblast cells (outer layer of blastocyst)

Question 4

what does hcG do

Answer 4

stimulates corpus luteum to contuse producing progesterone-causes morning sickness

Question 5

when does hcG levels peak

Answer 5

after 10 weeks, then falls to a low level; when placenta takes over oestrogen and progesterone production

Question 6

oogenesis occurs

Answer 6

in the ovaries–> half happens before birth and the rest during puberty

Question 7

stages of oogenesis

Answer 7

oogonium, primary oocyte, secondary oocyte

Question 8

polar bodies

Answer 8

not for fertilisation

Question 9

spermatogenesis

Answer 9

occurs in the testes (seminiferous tubules)–> controlled by GnRH, FSH and LH, testosterone and inhibin

Question 10

what hormones control spermatogenesis

Answer 10

lH, GnRH, FSH, testosteron and inhibin

Question 11

stages of spermatogenesis

Answer 11

spermatogenic, primary spermatocytes, secondary spermatocytes, spermatids and spermatozoa.

Question 12

Summary of menstrual cycle

Answer 12

1. GnRH produced by the hypothalamus stimulates the anterior pituitary to release and produce FSH and LH
2. FSH stimulates the maturation of follicles the ovaries.
3. due to low levels of oestrogen at the beginning of the cycle there are low levels of both of them (-ve)
4. however as the follicles grow and mature they produce more oestrogen and at a critical point, a surge of lh occurs (+ve)
5. this surge of LH causes ovulation
6. the empty follicle becomes the corpus lute

Question 13

why is the cL important

Answer 13

release progesterone, which (like oestrogen) causes the build up of the endometrium and at high level it gives negative feedback to the pituitary so no fish and lh is produced and ovulation doesn’t occur

Question 14

Male puberty starts at

Answer 14

11/12 when GnRH begins to be produced by the hypothalamus and this causes the production of sperm and sexual characteristics.

Question 15

‘weeks’ refer to

Answer 15

embryonic develop[,meant and differs from clincial/gestantional (since last period)

Question 16

embryonic period

Answer 16

1-8 weeks

Question 17

foetal period

Answer 17

9-37 weeks

Question 18

treatment often given to premature babies

Answer 18

cortisol–> helps with the development of lungs, when there isn’t enough surfactant, which reduces surface tension and therefore increases lung stability

Question 19

quickening occurs at

Answer 19

13-16 weeks

Question 20

first heart beat

Answer 20

week 3

Question 21

week 3

Answer 21

gastrulation

Question 22

week4

Answer 22

neurolation

Question 23

when does implantation occur

Answer 23

week 2

Question 24

implantation

Answer 24

trophoblast cells bind to endometrium of uterus

-enzymes are secreted (proteolytic) which break down the uterine wall

Question 25

ectopic pregnancy

Answer 25

embryo implants and begins developing prematurely in the fallopian tube

Question 26

why does the heart have to be one of the first organs to develop

Answer 26

as the embryo grows, simple diffusion of hormones and nutrients is not enough
-heart beat means they can be transported in the blood to developing organs

Question 27

Placenta (week 10)

Answer 27

• nutrition delivery
• excretion of waste product
• immunity
• endocrine function (HcG, progesterone, oestrogen)