Just so everyone knows what you are talking about
:
The vas deferens (plural: vasa deferentia), also called ductus deferens, (Latin: "carrying-away vessel"), and in lay talk sperm tube is part of the male anatomy of some species, including humans.
During ejaculation the smooth muscle in the wall of the vas deferens contracts reflexively, thus propelling the sperm forward. The sperm are transferred from the ductus deferens into the urethra, collecting fluids from the male accessory sex glands en route.
ADG