Physiology: Female reproduction organs

Question 1

Describe the structure of ovaries?

Answer 1

1. Surface = connective tissue capsule of simple cuboidal epithelium
2. Cortex - peripheral part, connective tissue containing ovarian follicles (one oocyte surrounded by single layer of cells)
3. Medulla - central part, connective tissue with blood vessels

Question 2

Describe the function of ovaries?

Answer 2

1. Oocyte production:
   ○ One mature egg per menstrual cycle
   ○ Majority of eggs perish during the cycle
   ○ Finite number
2. Steroid hormone production:
   ○ Estrogen develops female secondary sexual characters
   ○ Progesterone prepares endometrium for implantation
   50% of testosterone produced by ovaries before menopause

Question 3

Describe oogenesis

Answer 3

Before birth, most of primordial germ cell mitosis occurs before pausing at stage of first meiotic division until puberty
Second division starts after puberty (hormone secretion) and leads to release of one secondary oocyte in a menstrual cycle which is capable of fertilisation
Second meiotic division completes after fertilisation of oocyte with sperm

Question 4

Describe the chromosomal division during oogenesis

Answer 4

Before birth = 2n oogonium -mitosis> primary oocyte 2n

After puberty = meiosis continues -> secondary oocte 1n (polar body also has 1n)

Question 5

Describe the follicular development stage

Answer 5

Primordial follicles = primary oocyte arrested in first meiotic division surrounded by one layer of squamous pre granulosa cells.

Primary follicle- oocyte surrounded by zona and cuboidal granulosa cells

Secondary follicle- increased oocyte diameter and multiple layer of granulosa cells, resumption of first meiotic division

Tertiary /Graffian follicle- follicular fluid between the cells which coalesce to form antrum, completion of first meiotic division to form secondary oocyte and start of second meiotic division.

Further development after the secondary follicle stage requires stimulation from FSH