Testicular and Ovarian Function Flashcards
What are the two main functions of reproductive organs?
gametogenesis and secretion of hormones
Where is testosterone produced in the testis?
in the Leydig cells in the interstitial tissue
What is the role of mitotic division in gametogenesis?
to increase the number of germ cells
What are primary spermatocytes?
the product of mitotic division of spermatogonia
What are secondary spermatocytes?
the product of meiotic division of primary spermatocytes
What are spermatids?
the product of meiotic division of secondary spermatocytes
What are spermatazoa?
mature spermatids
When does spermatogenesis begin?
puberty
Why does one spermatogonia remain on the outside of the seminiferous tubule?
to maintain the germ cell line
When does oogenesis begin?
in fetal life
At what stage of division are primary oocytes arrested?
at prophase 1 of the first meiotic division
When does the primary oocyte complete its first meitotic division and what are the products?
at puberty in each menstrual cycle a few primary oocytes will complete their first meiotic division to become the secondary oocyte and the first polar body
When does the secondary oocyte begin and complete its second meiotic division and what are the products?
the second meiosis begins when the egg is released from the ovary - it divides into a mature ovum and a second polar body - however the second meiosis isnt completed until fertilisation occurs
How many mature ovum do you get from one primary oocyte?
1
How many mature spermatazoa do you get from one primary spermatocyte?
4
How many primary spermatocytes do you get from one spermatogonium?
4
What reproductive hormone is released from the hypothalamus?
GnRH
What reproductive hormones are released from the anterior pituitary from stimulation by GnRH?
LH and FSH
What peptide hormones are produced by the gonads?
inhibin and activin
What enzyme converts testosterone to DHT?
5 alpha reductase
What enzyme converts testosterone to estradiol?
aromatase
What is the role of sertoli cells?
to surround and support the sperm and regulate their development
What is the role of Leydig cells?
to secrete testosterone
What is the role of LH in males?
signals to the Leydig cells to produce testosterone
What is the role of FSH in males?
signals to the sertoli cells to release paracrine signals for spermatogenesis
How often is GnRH released?
it is constantly released in a pulsatile way
What is the role of inhibin?
negatively feedsback on FSH
Where does the mucus in semen come from?
the bulbourethral gland
Where do the buffers in semen come from?
the prostate and bulbourethral gland
Where does the fructose and vitamin C in semen come from?
the seminal vesicles