Epididymis epithelium. Transmission electron micrograph (TEM) of a section through a human testis (testicle), showing the epithelial lining of the epididymis. The function of the epididymis is to contribute to the maturation of spermatozoa (sperm cells). It is androgen (male sex hormone)-dependant. The cells have abundant organelles for biosynthesis of a wide range of proteins and many vesicles involved with absorption of luminal fluids and export of secretory products. Magnification x5600, when printed 10 centimetres wide.