Histology - Seminiferous Tubule
Seminiferous tubules.
- Lumen and basement membrane.
- Sustentacular cells are columnar with extensive cytoplasmic processes.
- Because sustentacular cells secrete substances that facilitate spermatogenesis and nurture the developing sperms, they are also referred to as "nurse" cells.
- Connected via tight junctions, which divides the tubule into basal and adluminal compartments.
- Intercellular junctions form the blood-testis barrier, which blocks toxins in the blood from the developing gametes.
- Spermatogenic series, aka, the male gametes in various stages of development
- Spermatogonia in basal compartment undergo mitosis to create primary spermatocytes, which reside within the adluminal compartment and give rise to secondary spermatocytes.
- Secondary spermatocytes undergo meiosis II to produce spermatids, which then form immature sperm. Notice that each successive stage moves closer to the lumen.
- Sperm are released into the lumen, and label their heads and tails.