The efferent ducts (also efferent ductules, ductuli efferentes, ductus efferentes, or vasa efferentia) connect the
rete testis
The rete testis ( ; : retia testes) is an anastomosis, anastomosing network of delicate tubules located in the hilum of the testicle (mediastinum testis) that carries spermatozoon, sperm from the seminiferous tubules to the efferent ducts. It is t ...
with the initial section of the
epididymis
The epididymis (; : epididymides or ) is an elongated tubular genital organ attached to the posterior side of each one of the two male reproductive glands, the testicles. It is a single, narrow, tightly coiled tube in adult humans, in length; ...
.
[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'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...
s and other large
mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...
s, 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 Mandible, lower jaws. About 40% of all mammal specie ...
s, whereby the 3–6 ductules merge into a single small ductule before 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 increases the concentration of luminal sperm. The epithelium is surrounded by a band of
smooth muscle
Smooth muscle is one of the three major types of vertebrate muscle tissue, the others being skeletal and cardiac muscle. It can also be found in invertebrates and is controlled by the autonomic nervous system. It is non- striated, so-called bec ...
that helps to propel the sperm toward the epididymis.
Additional images
File:illu_testis_cross_section.jpg
See also
*
List of distinct cell types in the adult human body
The list of human cell types provides an enumeration and description of the various specialized cells found within the human body, highlighting their distinct functions, characteristics, and contributions to overall physiological processes. Cell ...
External links
* – "Mammal, testis overview"
* – "Inguinal Region, Scrotum and Testes: Reflection of the Head of the Epididymis"
*
Diagram/Quiz (cancer.gov)researchgate
References
{{Reflist
Hess RA 2018. Efferent ductules: structure and function. Encyclopedia of Reproduction. Skinner MK. San Diego, Academic Press: Elsevier. 1: 270–278.
Scrotum