Male Reproductive Histology Flashcards
(43 cards)
What surrounds the testes?
Tunica albuginea
How is the mediastinum testis formed?
The mediastinum testis is a posterior thickening of the tunica albuginea.
Visceral and parietal layers of tunica vaginalis
Visceral layer of tunica vaginalis covers the tunica albuginea.
Parietal layer lines the scrotum.
What cells are part of the seminiferous epithelium?
Somatic Sertoli cells
Spermatogenic cells
Where are interstitial cells of Leydig found?
Between the seminiferous tubules.
Sertoli cells
Columnar cells w/ extensive processes that surround spermatogenic cells and occupy spaces between them.
Spermatogenic cells function
Replicate and differentiate into mature sperm
Which spermatogenic cells are considered to be most immature? Mature?
Where are they located?
Spermatogonia are most immature and are on the basal lamina.
Spermatids are most mature and they are on the apical portion of the Sertoli cells.
What separates the seminiferous epithelium into basal and luminal compartments AND is the site of the blood-testis barrier?
Sertoli cell-to-Sertoli cell junctional complexes
Where are spermatogonia and early spermatocytes restricted?
Where are mature spermatocytes and spermatids restricted?
The basal compartment (between SC-to-SC junctions and basal lamina).
The luminal compartment.
In which compartment does meiosis and spermiogenesis occur?
The luminal compartment
Sertoli cells function as:
“Nurse cells”.
They function in exchange of substrates/wastes.
Phagocytose cells that fail to differentiate.
What do interstitial cells of Leydig produce?
Testosterone
Type A spermatogonia
Clonally divide.
Generates copies of itself and/or differentiates into type B spermatogonia.
Type B spermatogonia
Divide (mitosis) and immediately enter meiotic prophase as primary spermatocytes.
Ensures 2x DNA when starting meiotic prophase.
Divisions of spermatocytes
Primary spermatocytes –> 2 secondary spermatocytes
Secondary spermatocytes –> 2 spermatids
Where are round (early) spermatids housed?
In the niches of the cytoplasm of Sertoli cells
Where are elongated (late) spermatids housed?
The crypts, or deep invaginations of Sertoli cells.
What is the process of releasing mature spermatids?
Spermiation
Phases of spermiation
Golgi phase - enzymes move golgi to acrosome. Axoneme begins to develop.
Cap phase - acrosome forms a cap. Spermatid rotates.
Acrosomal phase - Manchette develops. Axoneme extends and flagellum grows.
Maturation phase - unneeded cytoplasm is shed as residual body and intercellular bridges are lost. Mature, but not yet functional sperm released.
Middle piece of the tail of the sperm contains: (3)
Helical mitochondrial sheath
Axoneme
Outer dense fibers
Principal piece of the tail of the sperm contains: (1)
Central axoneme surrounded by a fibrous sheath which helps with motility.
End piece of the tail of the sperm contains: (1)
Only the axoneme
Sperm transport pathway
Straight tubules Rete testis Efferent ductules Epidydmal duct Vas deferens Ejaculatory duct
