During spermatogenesis, at which site does sperm gain motility?

During spermatogenesis, sperm gains motility primarily in the epididymis. This structure is a coiled tube located at the back of each testis and serves several crucial functions in the maturation of sperm. After sperm are produced in the seminiferous tubules of the testes, they are not immediately motile. It is within the epididymis that sperm undergo further maturation and gain the ability to swim, which is essential for fertilization.

The epididymis also serves as a storage site for sperm until ejaculation occurs. As sperm mature in this location, they develop the necessary characteristics, including the formation of the flagellum, which is vital for motility.

In contrast, while the testes are where sperm production begins, they do not contribute to sperm motility. Semen, which is the fluid containing sperm and other components, does not foster motility itself; rather, it serves as a medium for transport. The urethra is involved in the passage of sperm during ejaculation, but it is not the site where sperm gain motility. Thus, the epididymis is the correct answer as it is the specific site where sperm develop motility.