Male Reproductive Flashcards
function of the scrotum
keep testes away from body core to maintain lower temperature optimum for sperm production
order of sperm travel through testes
- made in seminiferous tubules
- travel through straight tubules
- collect in rete testis
- exit through efferent ducts
- store in head body and tail of epididymis
- travel through vas deferens
- join with seminal vesicle in ejaculatory duct
- run through prostate/prostatic urethra
- membranous urethra
- exit through spongy urethra
how are lobules of seminiferous tubules divided?
tunica albuginea continuous with septa that divide seminiferous tubules into 200-250 lobules
what is tunica vaginalis
an extension of the peritoneum that was picked up on the testes’ descent through abdomen, has parietal and visceral layers (mesothelial sac)
what is tunica albuginea made of
dense irregular connective tissue (is a tough capsule)
what does the mediastinum testis contain
rete testis, vessels, nerves (is a hilum)
what is the mediastinum testis
a posterior thickening of the tunica albuginea
what cells secrete testosterone
leydig or interstitial cells, are clusters within loose vascular connective tissues between seminiferous tubules
3 layers of seminiferous tubules
- innermost stratified seminiferous/germinal epithelium
- middle contractile myoid layer attached to well defined basal lamina
- outermost tinica propria - thin layer fibrous CT
what does the germinal epithelium contain
spermatogenic cells and sertoli cells
what does the tunica propria contain
isolated fibroblasts
what stimulates testosterone production in the leydig cells
LH
describe leydig cells
extensive SER, golgi, lipid droplets (bc steroid secreting), large round pale nuclei, prominent nucleoli, pale acidophilic cytoplasm
where are spermatogenic cells derived
embryonic yolk sac endoderm
how can spermatogenic cells be differentiated
size, nuclear morphology, position in germinal epithelium
chromosomes in stermatogonia
46, diploid 2N
what cell type is present prior to puberty?
spermatogonia ONLY
chromosomes in primary spermatocytes
46, diploid, 2N
what phase of cell division are primary spermatocytes in
frozen in prophase of meisosis I
what is the relationship between primary spermatocytes and sertoli cells and why
primary spermatocytes form tight junctions with sertoli cells to protect from immune system
what cells are rarely seen in the germinal epithelium and why?
secondary spermatocytes, because they rapidly undergo a second meiotic division immediately
chromosomes in secondary spermatocytes
23, haploid, N
chromosomes in spermatid
23, haploid, N
difference between spermatids and spermatozoa
spermatids are variable in size, have dark nuclei and are not in the lumen yet, spermatozoa have a characteristic flattened head and dark nucleus with flagella and are in the lumen