Reproductive system

Question 1

Hypothalamus releases …… which acts on ……

Answer 1

GnRH- Gonadotropin releasing hormone

Pituitary gland

Question 2

Pituitary gland releases ….. which acts on …..

Answer 2

Lutenising hormone, FSH

Gonads

Question 3

Gonads

Answer 3

Produce germ cells

Produce sex steroid hormones

Question 4

Ovaries release

Answer 4

Oestrogens (ERs- oestrogen receptors) eg oestrone, oestradiol
Progesterone (PRs)

Question 5

Testes release

Answer 5

Androgens: testosterone

Dihydrotestosterone (DHT) is the common form in the body

Question 6

seminiferous tubules

Answer 6

In the testes

The site of sperm production (spermatogenesis) and hormone synthesis

Question 7

2 cell types in the seminiferous tubules

Answer 7

Leydig- testoterone producing

Serroli- in wall of tubules where sperm are derived from

Question 8

Spermatogenesis

Answer 8

FSH/testosterone drive production of sperm

Testosterone acts locally on serrolis, and gets into bloodstream via testicular vein

Question 9

Precursors of androgens

Answer 9

cholesterol, pregnenolone, progesterone

Question 10

Androgens effect on Hypo

Answer 10

decr GnRH secretion

-ve feedback

Question 11

Androgen effects on Pituitary

Answer 11

decr LH secretion

-ve feedback

Question 12

Androgens effect on metabolism

Answer 12

‘anabolic steroids’
Protein anabolism
Bone growth
Stimulates erythropoietin

Question 13

Androgen effects on testes

Answer 13

spermatogenesis

Question 14

Androgens effect on male sex charateristics

Answer 14

Differentiation of male reproductive organs
Secondary sex characteristics
Sex drive

Question 15

Sertoli cells also release

Answer 15

Inhibin, -vely feeds back onto pituitary to inhibit production of only FSH

Question 16

Ovarian functions

Answer 16

Oogenesis
Maturation of the oocyte
Ovulation
Secretion of female sex steroid hormones

Question 17

Oogenesis

Answer 17

Ovum production
Occurs monthly in ovarian follicles
Part of ovarian cycle

Question 18

Ovarian cycle consists of

Answer 18

Follicular phase (preovulatory)
Luteal phase (postovulatory)

Question 19

The follicular phase

Answer 19

Maturation of primary follicles in under control of FSH

Follical cells develop into granulosar cells and follicle cells around the oocyte develop into theca cells

Question 20

Luteal phase

Answer 20

Ovulation and corpus luteum formation under control of LH
Corpus luteum starts to make progesterone once egg leaves
Corpus luteum forms albicans if egg doesn’t implant

Question 21

Functions of the uterus

Answer 21

• Muscular organ
• mechanical protection
• nutritional support
• waste removal for the developing embryo and fetus

Uterine cycle involves changes in the uterine wall

Question 22

Uterine wall has 3 layers

Answer 22

Myometrium- outer muscular layer
Endometrium- thin, inner glandular mucosa
Perimetrium- incomplete serosa continuous with the peritoneum

Question 23

Ovarian cycle summary

Answer 23

In the ovary the egg develops, released into fallopian tube- implants into uterus wall if meets a sperm
Uterus develops endometrium to receive implanted egg- shed if no egg

Question 24

Uterine cycle

Answer 24

repeating series of changes in the endometrium
Continues from menarche (1st menstruation) to menopause
3 stages: menses, proliferative phase, secretory phase

Question 25

Menses

Answer 25

Degeneration of the endo = menstruation

Question 26

Proliferative phase

Answer 26

Restoration of the endo

Question 27

Secretory phase

Answer 27

Endometrial glands enlarge and accelerate their rates of secretion

Question 28

FSH

Answer 28

stimulates follicular development

Question 29

LH

Answer 29

maintains structure and secretory function of corpus luteum

Question 30

Oestrogens

Answer 30

multiple functions

Question 31

Progesterones/Progestogens

Answer 31

Stimulate endometrial growth and secretion

Question 32

Hormonal control of ovarian function

Answer 32

Hypo secretion of GnRH, acts on pituitary to secrete FSH and LH FSH acts on granulosa cells, which influence oocytes and release inhibin- negatively feeds back onto pituitary (primarily FSH inhibition) LH acts on theca cells which release androgen substrate required for estrogen biosynthesis Oestrogen engatively feeds back onto Pituitary and hypothalamus

Question 33

GnRH

Answer 33

Function of gonads controlled by hypo and AP, under influence of higher brain centres in the cortex Leads to pulsatile GnRH release (freq 60-90 mins) and hence incr in pulsatile gonadotrophin secretion from the pituitary at puberty

Question 34

Ovulation day

Answer 34

14

Question 35

When is LH highest

Answer 35

day 14