Reproductive Physiology - 1 Flashcards
Where does the process of oogenesis occur?
In the ovarian follicles
What are the three layers of the ovaries? Brief description of composition?
Surface - connective tissue capsule comprised of simple cuboidal epithelium
Cortex (peripheral) - connective tissue containing ovarian follicles
Medulla (inner) - connective tissue rich in blood vessels
What are the main functions of the ovaries?
Oocyte production - maturation of eggs during menstrual cycle
Steroid hormone production - estrogen & progesterone (and testosterone to a lesser extent)
What are the functions of estrogen and progesterone?
Estrogen - development & maintenance of female secondary sexual characteristics (breast / hair / body structure)
Progesterone - prepares endometrium for implantation in every menstrual cycle
When does promordial germ cell mitosis occur in females? What happens to the cells after this?
Primordial germ cell mitosis occurs during fetal life of the female
These cells are then arrested at the first stage of meiotic division until puberty
What is an oogonium? (oogonia - plural)
The immature female reproductive cells that give rise to primary oocytes via mitosis in the fetal life of females
What is a primordial follicle composed of?
A primary oocyte surrounded by a single layer of epithelium (squamous pre granulosa cells)
What triggers the conversion of a primordial follicle to a primary follicle?
Secretion of FSH and LH at sexual maturity
When is the first meiotic division of the primordial follicle complete? When is the second meiotic division complete?
By the time it is a secondary follicle
The secondary follicle is the follicle that is capable of releasing a mature oocyte that can be fertilized
The second division completes after the oocyte is fertilized by sperm (not gonna bother much with this?)
How many primordial follicles are activated each menstrual cycle?
Around 20, but only one makes it to maturity - the dominant follicle
Describe the follicular development stages
Oogonia
Primordial follicle
Primary follicle - oocyte surrounded by zona and cuboidal granulosa cells
Secondary follicle - increased oocyte diameter and multiple layers of granulosa cells
Tertiary / Graffian Follicle - follicular fluid between cells which coalesce to form the antrum
Describe the products of the meiotic division of the primary follicle
Secondary follicle - containing oocyte and majority of cellular mass
Polar body - residual body containing the haploid genome that needed to be rid of before fertilization