The location of the efferent ducts within an adult human testicle
Vertical section of the testis, to show the arrangement of the ducts. (Labeled as vasa efferentia as top center.)
|Latin||Ductus efferentes testis|
There are two basic designs for efferent ductule structure:
- a) multiple entries into the epididymis, as seen in most large mammals. In humans and other large mammals, there are approximately 15–20 efferent ducts, which also occupy nearly one third of the head of the epididymis.
- b) single entry, as seen in most small animals such as rodents, whereby the 3–6 ductules merge into a single small ductule prior to entering the epididymis.
The ductuli are unilaminar and composed of columnar ciliated and non-ciliated (absorptive) cells. The ciliated cells serve to stir the luminal fluids, possibly to help ensure homogeneous absorption of water from the fluid produced by the testis, which results in an increase in the concentration of luminal sperm. The epithelium is surrounded by a band of smooth muscle that helps to propel the sperm toward the epididymis.
- Anatomy photo: Reproductive/mammal/testis0/testis4 - Comparative Organology at University of California, Davis – "Mammal, testis overview"
- Anatomy photo:36:10-0100 at the SUNY Downstate Medical Center – "Inguinal Region, Scrotum and Testes: Reflection of the Head of the Epididymis"
- Histology image: 16903loa – Histology Learning System at Boston University
- Diagram/Quiz (cancer.gov)