Repro

Question 1

What is the embryonic origin of the urogenital ridge

Answer 1

intermediate mesoderm region

Question 2

What does urogenital ridge give rise to?

Answer 2

Embryonic kidney

Gonad

Question 3

What drives the male gonad development?

Answer 3

SRY gene 
on short (p) arm of Y chromosome

Question 4

What happens to the gonad under the Y chromosome influence?

Answer 4

Primodal germ cells colonise the medulla

-> testis and thick tunica albuginea develop

Question 5

What happens to the gonad without the Y chromosome influence

Answer 5

Primodal germ cells colonise the cortex

-> medullary cords degenerate and ovaries develop

Question 6

What makes up the mesonephric/Wolffian duct ?

Answer 6

Urogenital sinus and anus divided by uroqrectal septum

Question 7

What happens to the mesonephric/wolffian ducts under the influence of testosterone?

Answer 7

mesonephric duct sprouts ureteric buds
they make separate openings
->prostate and prostatic urethra forms

Question 8

What happens to the mesonephric/ wolffian ducts without the influence of testosterone?

Answer 8

mesonephric duct sprouts ureteric buds

ureteric bud expands and mesonephtic duct regresses

Question 9

Embryonic origin of the uterus and cervix?

Answer 9

Paramesonephric duct

AKA Mullerian duct

Question 10

What prevents the uterus from forming in males?

Answer 10

Mullerian Inhibiting Substance

secreted by sertoli cells

Question 11

What influences the development of the external genitalia?

Answer 11

Dihydrotestosterone -> male

Question 12

What attaches the testis to the inguinal region?

Answer 12

gubernaculum

Question 13

What prevents the ovary descend past the pelvic brim

Answer 13

paramesonephric ducts

Question 14

Male gametes formation

Answer 14

Mitosis:
spermatogonia (before birth) -> raw material
-> A1 spermatogonia
-> primary spermatocytes (linked by cytoplasm)
Meiosis:
spermatogenesis -> spermatids (remodelled to..)
-> spermatozoa

Question 15

Semen contains secretions of (4):

Answer 15

seminal vesicle (60% of vol)
prostate (20%)
bulbs-urethral glands
+ sperm

Question 16

Female gametes formation

Answer 16

Oognia (primordiale germ cells in gonadal cortex) mitosis by mid-gestation.

• > primary oocyte (meiosis arrested at prophase 1)
• > primordial follicle (oocyte surrounded by granulose cells layer)
• > ovum

Question 17

Ovum production

Answer 17

small number of primordial follicles begin to develop further at the beginning of the cycle -> 1/2 complete the the development

• > pre-antral ovum (indeed. of hormones)
• > antral ovum (LH and FSH cause…)
• > pre-ovulatory follicle

Question 18

Pre-ovulatory follicle structure

Answer 18

theca (externa and int)
granulose cells
Antrum
primary oocyte

Question 19

Origin of anterior pituitary

Answer 19

ratheke’s pouch

endocrine gland

Question 20

Control of reproduction: the axis

Answer 20

hypothalamus -> GnRH
ant. pit. -> FSH and LH
Gonads

Question 21

What has -ve feedback on GnRH?

Answer 21

testosterone

oestrogen (moderate levels)

Question 22

What has +ve feedback on GnRH?

Answer 22

high levels of oestrogen

Question 23

What effect does progesterone has on GnRH production?

Answer 23

Progesterone reduces the effects of oestrogen
-> GnRH can’t be +vely stimulated
-> no LH surge
also reduced frequency go GnRH pulses

Question 24

What has -ve feedback on LH and FSH secretion?

Answer 24

testosterone

moderate oestrogen levels

Question 25

What has +ve feedback on LH and FSH secretion?

Answer 25

high oestrogen levels

Question 26

Role of inhibit in control of reproduction

Answer 26

selective FSH inhibition -> LH, FSH proportions altered inhibit levels increase as the rate of development increases

Question 27

Male control of reproduction is under what feedback?

Answer 27

-ve

Question 28

FSH effects in males

Answer 28

``` Sertoli cells (nursing cells) -> inhibin ```

Question 29

LH effects in males

Answer 29

Leydig cells (endocrine cells) - > testosterone - > spermatogenesis stimulation

Question 30

FSH effects in females

Answer 30

``` Granulosa cells (surrounding cells) -> stimulated to proliferate ```

Question 31

LH effects in females

Answer 31

``` Theca cells -> theca interna stimulation -> oestrogen -> inhibin -> FSH release suppressed Maintains corpus lutem ```

Question 32

LH surge effects in females

Answer 32

ovulation | theca externa's collagen breaks down and ovum is released

Question 33

Oestrogen effects in females

Answer 33

endometrial thickening myometrium stimulation and activation (contractions) thin, alkaline mucus (sperm sticks)

Question 34

Progesterone effects in females

Answer 34

acts on cells that have been exposed to oestrogen endometrium dev. into secretory form myometrium thickening and loss of motality thick, acid mucus (mucus cap formed) mammary tissue changes

Question 35

Pre-menopause changes

Answer 35

``` follicular phase shorthens -> ovulation early or absent less oestrogen secreted LH and FSH increase (FSH more) reduced fertility ```

Question 36

Effects of menopause

Answer 36

``` vascular changes -> hot flushes oestrogen sensitive tissues -> regression of endometrium and myometrium -> thinning of cervix bone -> increased reabsorption ```

Question 37

Testis structure

Answer 37

consist of seminiferous tubules tunica albuginea and tunica vasculosa leydig cells -> testosterone

Question 38

Function of leydig cells

Answer 38

testosterone secretion

Question 39

Germ cells at different stages of development

Answer 39

spermatogonia spermatocytes spermatids

Question 40

Testis: nursing cells

Answer 40

Sertoli cells

Question 41

What is epididymis formed of?

Answer 41

Rete testis- seminiferous tubules | they merge together to form epididymis

Question 42

Epididymis function

Answer 42

first part: absorptive function - digestion of the residual bodies lost from sperm during maturation epithelial cells- secretory func. - proteins which contribute to sperm maturation

Question 43

Epididymis continues as...

Answer 43

vas deferens

Question 44

Vas deferens function

Answer 44

transport of germ cells from the epididymis to the ejaculatory duct

Question 45

Seminal vesicle: what is it?

Answer 45

outgrowths of ductus defers | coiled gubulocacular glands

Question 46

Seminal vesicle: function

Answer 46

secretes fluid which forms bulk of the ejaculate | not storage site for sperm