Male Reproductive NEW Flashcards
spermatogonia are made where in the seminiferous tubules
the basal layer
what stimulates leydig cells to make testosterone
LH
what do sertoli cells secrete
FSH and inhibin
when do interstitial cells of Leydig begin to secrete
during puberty
what are round and polygonal in shape and have a very large nucleus as well as a lot of mitochondria and well developed golgi apparatus
SER and many lipis droplets
Leydig Cells
what is the main gland in charge of stimulating the production of testosterone
pituitary gland
what cells surrond the epithelium of seminiferous tubules
myeloid cells
what is the epithelium of seminiferous tubules
stratified
where are spermatozoa produced
seminiferous tubules
how long are seminiferous tubules
30-70 cm long
150-250 um diameter
what are the purpose of myloid cells in seminiferous tubules
they resemble smooth muscle and they help to squeeze
what do seminiferous tubules become continuous with
tubuli recti
what is the epithelium of tubuli recti
cuboidal
tubuli recte lead to what
rete testis
what are the network of epithelial-lined channels in the mediatinum of the testis
rete testis
what lead from the rete testis into the epididymis
ductli efferentes
what are the 2 cells in seminiferous epithelium
spermatogonic cells and sertoli cells
how thick is the epithelium of the seminiferous tubules
4-8 cell layers thick
what cells are columnar and extremly complex in shape and extend from the basil lamina to the lumen
sertoli cells
what envelopes the developing germ cell and has irregular outlined apical and lateral plasma membrane
sertoli cells
what cells have an extensive SER and Golgi
sertoli cells
what has a large nucleouls and a pale nucleus
sertoli cells
seroli cells form occluding junctions and this does what
divids the lumen of the seminifeorus tubule into a basal and an adluminal compartment
what is responsible for establishing a blood-testis barrier
zonulae occludentes
what cells phagocyte excess cytoplasm
sertoli cells
sertoli cells secrete a fluid in the seminiferous tubules tht does that
transfers the spermatozoa to the genital ducts
what does androgen binding protein do
it binds testosterone and concentrates it to permit sperm maturation
what does inhibin do
inhibits release of FSH from anterior pituritary gland
what is the other of sperm
- spermatogonia
- primary spermatocyte
- secondary spermatocyte
- spermatid
- spermatozoa
spermatogenesis takes how many days
64
the daughter cells of spermatogenesis remain connected to each other by intercellular bridges froming what
syncytium
what may be responsibel for synchronous developemnt of germ cells along one seminiferous tubule
syncytium
when is syncytium disrupted
at the end of spermatogenesis and the spermatozoa are released
what are the three types of spermatogonia
pale type a
dark typ a
dark type b
what can pale type a spermatogonia do
they can make more type a or differentiate into type b
what do dark type a do
they can only regenerate more type a
how many chromosomes do primary spermatocyts have
they are diplod 46
what are the largest germ cells in the seminiferous epithelium
primary spermatocytes
how long does prophase take
22 days
what is the 1st meiotic division
prophase
what does the 1st meiotic division result in
secondary spermatocytes
how many chromosomes are in a secondary spermatocyte
23-haploid
what is the diameter of spermatid
7-8 um
the nuclei of spermatids often display what
condensed regions of chromatin
what have a pair of centrioles, mitochondria, free ribosomes, SER and well developed golgi
spermatids
when are acrosome and sperm tail formed
during spermiogenesis
what are the 4 phases of spermiogenesis
golgi
cap
acrosome
maturation
what phase of spermiogenesis is characterized by the formation of proacrosomal granules in the golgi complex
golgi phase
what do pracrosomal granules do ( golgi phase)
they come together to form one acrosomal granule that is inclosed in an acrosomal vesicle which will become attached to the anterior end of the nuclear envelope
what do the centrioles do in the golgi phase
migrate away from nucleus to form flagellar axoneme and then retreat towards the nucleus
what assist in forming the connecting piece associated with the tail of the sperm
centrioles
what phase involves the expansion of the acromsomal vesicle over much of the nucleus to make the acrosomal cap
cap phase
what phase is characterized by the nucleus becoming condensed and flatened, mitochondria aggreating around the proximal portion of the flagellum to form the middle piece and elongation of spermatid
acrosome phase
by the end of the acrosome phase the spermatids are oriented how
with their acrosomes pointing toward the base of the ST
what is the phase that is characterized by excess cytoplasm being discarded and the removal of the intercellular bridges and the cytoplasm being phagocyted by the sertoli cells
maturation phase
when is the maturation stage completed
when nonmotile sperm are released ( tail first) into the lumen of the seminiferous tubule
what does the cycle of seminiferous epithelium refer to
the wavelike sequence of maturation that happens in the seminiferous tubles
one cylce is the reappearnce of what
identical cell associations within the epithelium
one cycle happens how many days in humans
16- thats why you need four for sperm to be made (64)
what temperature is critical for sperm
35 C
the pampiniform plexus of veins that wrap around the testicular artery do what
function to dissipate heat and keep testis at 35 C
when the temp is below 35 C what brings the testis close to the body wall to increase the temperature
cremaster muscle
what cells are important for secondary sex characteristics
interstitial cells of Leydig
what acts on sertoli cells to synthesizes androgen binding protein
FSH
increased testosterone levels inhibit LH but what about when it comes to FSH
inhibin has to inhibit FSH ( that is made by the sertoli cells)
what conveys the spermatozoa to the outside of the body
genital ducts
where do genital ducts extend from
the ST to the urethra
