Reproductive Endocrinology

Question 1

Name the earliest recognisable germ cell.

Answer 1

Primordial germ cell

Question 2

2 polar bodies in the germ cell signifies what?

Answer 2

sperm entry and the completion of the 2nd meiotic division

Question 3

In what phase of the ovarian cycle are oestrogen and progesterone secreted in? What is the signficance of their secretion?

Answer 3

Oestrogen - Follicular phase
Progesterone - Luteal phase
essential for preparation of uterine lining for implantation

Question 4

Degeneration of corpus luteum signals what? What does it degenerate to?

Answer 4

Start of a new follicular phase - fertilisation did not occur
Degenerates to the corpus albicans

Question 5

If fertilisation has occured what does the corpus leuteum do?

Answer 5

Corpus luteum persists and produces increasing quantities of progesterone and oestrogen until after pregnancy

Question 6

What does the hypothalamus secrete that acts on the anterior pituitary to produce hormones?

Answer 6

GnRh

Gonadotrophin releasing hormone

Question 7

What does the anterior pituitary release?

Answer 7

FSH 
LH 
GH 
ACTH 
TSH

Question 8

What does the posterior lobe of the pituitary gland secrete?

Answer 8

ADH

Oxytocin

Question 9

What separates the hypothalamus in two?

Answer 9

The 3rd ventricle

Question 10

When GnRH acts on the anterior pituitary which hormones are released?

Answer 10

FSH - follicle stimulating hormone

LH - lutenizing hormone

Question 11

What is the function of FSH?

Answer 11

Acts on ovary

Stimulates development of follicles

Question 12

What is the function of LH?

Answer 12

Acts on ovary

Stimulates follicle maturation, ovulation and development of the corpus luteum

Question 13

FSH and LH stimulate the secretion of what and stimulate what?

Answer 13

Oestradiol and stimulate ovulation

Question 14

What is the function of the theca cells?

Answer 14

Produce androgen which is converted by the granulosa (aromatase) to oestradiol

Question 15

What is the function of oestradiol?

Answer 15

Thickens endometrium

Thins cervical mucus

Question 16

Oestrogen does what to the FSH production by the anterior pituitary? What does this do?

Answer 16

Suppresses it

Allows the selection of dominant follicle

Question 17

The high levels of oestrogen at mid cycle cause what?

Answer 17

Cause the hypothalamus to release GnRH

Causes a surge in release of FSH and LH from the anterior pituitary

Question 18

After ovulation what happens to the levels of LH and FSH?

Answer 18

Decrease

Question 19

If fertilisation occurs, what does the developing embryo produce? What are their functions?

Answer 19

hCG (chorionic gonadotrphin) - Functions to maintain the corpus luteum
Progesterone - functions to support pregnancy and suppress ovulation

Question 20

When does the placenta take over the role of producing progesterone and what happens to the corpus luteum?

Answer 20

6 weeks

Corpus luteum degenerate to the corpus albicans

Question 21

Which hormones stimulate spermatogenesis?

Answer 21

FSH and testosteroe

Question 22

Which hormone stimulates testosterone secretion?

Answer 22

LH

Question 23

What decreses secretion of FSH?

Answer 23

Inhibin

Question 24

Testosterone does what to the releasing of GnRH and LH?

Answer 24

Decreases it - negative feedback

Question 25

Where is inhibin and androgen binding globulin (ABG) produced?

Answer 25

Sertoli cell in seminiferous tubule

Question 26

Which part of the embryo impants on the wall of the uterus?

Answer 26

Blastocyst