The efferent ducts (or efferent ductules or ductuli efferentes or ductus efferentes or vasa efferentia) connect the
rete testis with the initial section of the
epididymis
The epididymis (; plural: epididymides or ) is a tube that connects a testicle to a vas deferens in the male reproductive system. It is a single, narrow, tightly-coiled tube in adult humans, in length. It serves as an interconnection between t ...
.
[Hess 2018]
There are two basic designs for efferent ductule structure:
* a) multiple entries into the epididymis, as seen in most large mammals. In
human
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...
s and other large
mammals, there are approximately 15 to 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
rodent
Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are roden ...
s, where by 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
Smooth muscle is an involuntary non- striated muscle, so-called because it has no sarcomeres and therefore no striations (''bands'' or ''stripes''). It is divided into two subgroups, single-unit and multiunit smooth muscle. Within single-unit ...
that helps to propel the sperm toward the epididymis.
Additional images
File:illu_testis_cross_section.jpg
External links
* – "Mammal, testis overview"
* – "Inguinal Region, Scrotum and Testes: Reflection of the Head of the Epididymis"
*
Diagram/Quiz (cancer.gov)
References
{{Reflist
Hess RA 2018. Efferent ductules: structure and function. Encyclopedia of Reproduction. Skinner MK. San Diego, Academic Press: Elsevier. 1: 270-278.
Scrotum