Flashcards in Male Reproductive Deck (77)
What does the male reproductive system consists of (5)?
2) genital ducts
3) seminal vesicle
What are the accessory glands (2)?
1) seminal vesicle
Dense irregular collagenous connective tissue capsule that encloses each testis
Thickened portion of the tunica albuginea where epididymis attach
Mediatinum testis gives rise to incomplete connective tissue septa that radiate into the testis and further subdivides into...
~250 lobules called lobuli testis
Layer of loose CT deep to the tunica albuginea and has a rich vascular supply known as the vascular capsule of the testis
What does each lobule of lobuli testis contain (3)?
1) 1-4 seminiferous tubules
2) interstitial cells of Leydig
3) loose CT stroma
What's the function of seminiferous tubules?
site of where spermatogonia differentiate into spermtazoa
What's the function of interstitial cells of Leydig?
produce and secrete testosterone
Where are interstitial cells of Leydig in reference to seminiferous tubules and CT stroma within lobuli testis?
interstitial cells of Leydig are scattered within the CT stroma, which surrounds seminiferous tubules
What are the three layers to seminiferous tubules?
1) tunica propria
2) basal lamina
3) seminiferous epithelium
What is in the tunica propria of seminiferous tubules?
thin CT layer consist of type 1 collagen with 3-5 layers of myoid cells
What are myoid cells?
they are contractile smooth muscle cells within the tunica propria of seminiferous tubules
What's the function of myoid cells?
rhythmic contractions that produce peristaltic waves to move spermatozoa through the seminiferous tubules
Does basal lamina of seminiferous tubules contain cells?
NO, it is acellular
What are the two cell types found in seminiferous epithelium?
1) spermatogenetic cells
2) Sertoli cells
Where does differentiation of spermatogenetic cells start and end within the seminiferous epithelium?
they start at the periphery of the epithelium then progress toward the lumen
Describe the appearance of Sertoli cells
tall, columnar cells that have highly folded apical and lateral cell membrane
nuclei are clear, ovoid or triangular
Note: these cells run the entire length of the epithelium (unlike spermatogenetic cells)
Do Sertoli cells replicate?
Not after puberty
What type of cellular junctions do Sertoli cells have?
extremely tight zonula occludens junctions
What's the purpose of the tight junctions in Sertoli cells?
they bind the lateral cell membranes of adjacent Sertoli cells together to compartmentalize the seminiferous epithelium into 2 compartments
What are the two compartments that is compartmentalized by the tight junctions?
1) basal epithelial
What is the blood-testis barrier?
occludens jucntions create this barrier to separate the antigenic spermatogenetic cells from the immune system
Why are spermatogenetic cells antigenic and specifically which ones?
they are haploid (1n):
secondary spermatocytes (1n-2d)
spermatids and sperm (both 1n-1d)
What can phagocytose spermatid remnants?
What does testosterone bind to and what releases it?
ABP (androgen-binding protein) released by Sertoli cells
What's the purpose of ABP?
Which compartment of seminiferous epithelium is considered immuno-priviledged? Why?
luminal compartment because it contains the spermatogenetic cells
What's inside the basal epithelial compartment of seminiferous epithelium?
1) spermatogonia and early primary spermatocytes
2) blood, ions, and other nutrients (aa's, carbs and proteins)