(C14,15) Slide 5: Testis and epididymis - H & E

Start by looking at the slide without the microscope. The oval structure is a portion of the testis, and the C-shaped structure that wraps around it is the epididymis. The epididymis is a long, coiled tube, and therefore, you see many sections through the same structure (C14). It has sperm in its lumen, and is lined by pseudostratified columnar epithelium. At first glance the epithelium may appear to be stratified, but take a closer look (C15). All cells touch the basement membrane. There are two rows of nuclei: one continuous row of nuclei toward the apex, and one staggered row of nuclei at the base. The basal cells cannot be packed together tightly because they must leave room for processes of the apical cells to reach the basement membrane. On the apex, there is a blur of stereocilia - long microvilli that increase the surface area. The terminal web and terminal bars are visible at the apical ends of the cells. The complete name of this epithelium is pseudostratified columnar epithelium with stereocilia.

Remember that stereocilia are rare and that the male reproductive system is the only place in this course where you will encounter them. So, if you (i) see a fuzzy border at the apex of the epithelium, (ii) can make out individual apical projections, and (iii) sperm are present, then there are stereocilia on the epithelium, and you must include "with stereocilia" in the name of that epithelium.