- Describe the structure and cell types of the seminiferous tubules
- Structure
- Seminiferous epithelium: Complex stratified epithelium composed of Sertoli cells and spermatogenic cells
- Tunica propria: 3 – 5 layers of connective tissue with myoid cells and collagen fibrils external to the basal lamina of the seminiferous tubules
- Cell types
- Sertoli cells: Supporting or Sustentacular cells. Columnar cells with apical and lateral processes that surround spermatogenic cells. Form the tubules.
- Spermatogenic cells: Regularly replicates and differentiates into mature spermatids.
- Spermatogonia type A pale
- Spermatogonia type A dark
- Spermatogonia type B pale
- Spermatids
- Spermatozoa
- Structure
Distinguish between spermatogonia type A and type B
| Spermatogonia A dark (Ad) | Spermatogonia A pale (Ap) | Spermatogonia B |
|---|---|---|
| Ovoid nuclei | Ovoid nuclei | Spherical Nuclei |
| Densely staining basophilic chromatin | Lightly staining chromatin | – |
| Finely granular chromatin | Finely granular chromatin | Condensed chromatin |
| Reserve stem cells | Renewal stem cells | – |
| Divide at irregular intervals | Divides at regular intervals | – |
| Forms Ad or Ap | Forms B | Forms spermatocytes |
- What constitutes the blood-testis barrier?
- Sertoli cell – sertoli cell junctional complexes
- Describe the zonation of the prostate gland.
- Central zone (25%): Surrounds ejaculatory ducts as they pierce the glad
- Peripheral zone (70%): Surrounds the central zone and occupies posterolateral parts of the glans. Most susceptible to prostatic carcinoma
- Transitional zone (5%): Surrounds prostatic urethra. Undergoes Benign prostatic hyperplasia
- Periurethral zone: contains mucosal and submucosal glands. Stroma undergoes pathological growth during the late stages of BPH
- Which zone of the prostate is most likely to undergo benign hyperplasia
- Transitional zone
- Which zone of the prostate is most likely to undergo cancerous change
- Peripheral zone
