Nevertheless ascidians can usually be distinguished from other invertebrates by the presence and form of incurrent and
excurrent siphons.
These species all share, besides the laminar division, open primary areoles, with noncostal areoles including two or more
excurrent veinlets, and sori in a terminal position on the veinlets.
In these taxa, the male inserts the
excurrent siphon into the incurrent siphon of the female before releasing sperm, resulting in internal fertilization.
GPxs have a particularly important role, as several GPx proteins reside in the spermatozoa plasma membrane, and are found in close physical proximity to spermatozoa as they transit through the
excurrent duct system.
Bunick et al., "Estrogen receptor (a and [beta]) expression in the
excurrent ducts of the adult male rat reproductive tract," Journal of Andrology, vol.
Samples of spermatozoa and eggs were taken using pipettes positioned directly above the
excurrent siphon of spawning clams and were immediately examined.
Longer abstinence intervals reward men with poor sperm production, because sperm accumulate in the
excurrent ducts for 7 days or more of sexual abstinence; and otherwise penalize men with good sperm production, because after 3 days or less of abstinence, their
excurrent ducts are probably full (1).
We have presented the proportion covering the aerial parts of tree species respectively as
excurrent crown and decurrent crown for Common Cypresses and old Rubber trees [9].
For unusual presentation in inguinal part of
excurrent ductal system as a primary representative site and tuberculosis of the same presenting with suppuration in this region which is not reported in the literature.
Epididymis is the basic segment of the
excurrent duct system in the reproductive tract of male goat where maturation and storage of spermatozoa occur under androgenic control (Robaire et al., 2006).
The Wabash pigtoe releases small pelagic conglutinates, while the monkeyface displays a modified
excurrent aperture that acts as a lure (Crownhart et al., 2006; Barnhart et al., 2008).
The bivalves apparently do not benefit from the water current created by the host, because adults are usually not close to the incurrent or
excurrent flow and because they are in very different positions in the host (Fig.