E3 Male reproductive system Flashcards
function of male reproductive tract
- production of sperm (spermatogenesis)
- delivery of sperm to the female
primary male reproductive organ
testes
secondary male reproductive organs, also state their function
support the function of the testes
penis
scrotum
epididymis
vas deferens
seminal vesicles
prostate gland
what are the testes?
- male gonads
- 250-300 compartments each containing clusters of Leydig and Sertoli cells
what are the testes responsible for?
- sperm production
- development of sperm
- spermatogenesis
- delivery of sperm to female
where are sperm stored after they have fully developed?
- when fully developed they are deposited into the lumen of the epididymis
- they then move down the reproductive tract when it is time for delivery to the female
describe spermatogenesis
- production of male gametes from primordial germ cell
- original cells undergo division and development and post developmental modifications to produce specialised sperm cells
- involves seminiferous tubules
- cells produce and mature the sperm
what cells produce and mature the sperm in spermatogenesis?
Sertoli cells
what cells are responsible for the production of testosterone?
Leydig cells
where are the Leydig cells positioned?
interstitially and between Sertoli cells
state some cells and features of the testes
- Leydig cells
- Sertoli cells
- smooth muscle
- blood-testis barrier
location and function of Leydig cells
- interstitial cells found in the gaps of the seminiferous tubules
- secrete testosterone
structure and basic function of Sertoli cells
- epithelial cells
- support sperm development and maturation
- arranged in circular arrangement to create the seminiferous tubule and a hollow lumen which sperm are then released into when fully mature
function of smooth muscle in testes
- peristalsis
- propel sperm towards egg
structure and function of blood-testis barrier
- prevents sperm getting into the general circulation
- tight junctions
- luminal compartment and basal compartment so nothing produced in testes can leak into circulation
in depth functions of Sertoli cells
- support sperm development by providing nutrients in response to testosterone secreted by Leydig cells
- secrete luminal fluid in which sperm develop
- secrete androgen-binding protein into lumen of seminiferous tubules
- target cells for testosterone and FSH
- secrete inhibit (hormone of negative feedback loop for FSH)
- secrete Müllerian inhibiting substance (MIS) in foetal life
- form blood-testis barrier
explain the function of Sertoli cells: secrete androgen-binding protein into lumen of seminiferous tubules
- acts as an androgen buffer
- facilitate production and delivery of sperm into the epididymis
- helps maintain steady androgens in lumen
describe the conversion of spermatid to sperm
- migration and movement of cell from basal membrane of Sertoli cells down seminiferous tubule into inner lumen
- differentiation gives the sperm the structure for their function
what is the male copulatory organ?
- penis
- penetrates vagina and deposits sperm
describe erection and ejaculation
- during sexual arousal, penis undergoes erection
- blood flow to penis increases to make sure it undergoes erection
- engorges erectile tissue
- penis swells and elongates
- during ejaculation, sperm ejects through urethra
describe the scrotum
- suspended beneath penis
- houses testes
what is the purpose of the scrotum?
- sperm can’t mature at normal body temp
- scrotum has thin-walled sac that makes testes a couple of degrees cooler than normal body temp
how does the scrotum regulate temperature in the cold?
dartos and cremaster muscles contract
describe the scrotal sac
- lack of fat
- excess of sweat glands
- wrinkled to increase surface area (to increase transfer of heat to ensure temperature doesn’t drop too far when it is cold)
- convoluted network of arteries and veins (allows maintenance of homeostasis temperature)