Female reproductive physiology

Question 1

What is produced in the ovaries?

Answer 1

Gametes as well as oestrogen and progesterone, female sex hormones that underly development of gamete and uterine wall

Question 2

What is the role of the fimbriae of the fallopian tubes?

Answer 2

Closely assc. with ovaries, so eggs can pass through and become fertilised or if not exit via uterus > cervix > vagina

Question 3

What are the steps of oogenesis?

Answer 3

Oocytes mature from oogonia before birth- undergoes mitotic division > inc. number potential oocytes

• 1st meiotic division before birth > primary oocytes- all divisions stop until puberty
• After puberty meiosis I > 2 distinct cells: secondary oocyte (Haploid) and polar body (mostly chromosomal material)

Question 4

What are the most basic ovarian structures and what do they consist of?

Answer 4

Primordial follicles- consist of primary oocyte surounded by single layer of cells (granulosa) sitting upon CT basal lamina

Question 5

How are theca cells and the zona pellucida created?

Answer 5

Theca cells- basal lamina cell differentiation

Zona pellucida- multiplication of granulosa celas which multiply and create mucopolysaccharide around ovum

Question 6

How are theca cells and the zona pellucida created?

Answer 6

Theca cells- basal lamina cell differentiation

Zona pellucida- multiplication of granulosa celas which multiply and create mucopolysaccharide around ovum

Question 7

What happens at the start of each ovarian cycle?

Answer 7

some primordial follicles enlarge, antrum forms filled w follicular fluid from granulosa cells

Question 8

What happens to these enlarged primordial follicles?

Answer 8

Only one develops further- graafian follicle- other regresses
Graafian enlarges, theca cells differentiate (t. interna/externa)

Question 9

What happens on day 14 of the follicular phase?

Answer 9

Follicle so large it distorts ovarian surface- fluid accumulation and proteolytic enzyme activity > rupture
secondary oocyte released to fimbriae of FT (ovulation)

Question 10

Luteal phase (days 14-28)

Answer 10

Follicle fills with blood (corpus haemorrhagicum)
Granulosa/theca cells swell up, become rich in yellow fatty deposits + blood vessels infiltrate follicle ( VEGF)
Now the corpus luteum. If no fertilisation CL degenerates > menses

Question 11

What is GnRH?

Answer 11

Gonadotrophin releasing hormone (GnRH) is secreted by hypothalamus > hypophyseal portal circulation > FSH and LH from ant pituitary.

Question 12

What does FSH do in the follicular phase?

Answer 12

Encourages cell division and oestrogen secretion by granulosa cells