What is the function of the epididymis?

The epididymis plays a vital role in the male reproductive system, particularly regarding sperm maturation and storage. Located at the back of each testis, the epididymis provides an environment for sperm to develop and mature after they are produced in the testes.

Once sperm are produced, they are relatively immature and cannot yet fertilize an egg. The epididymis allows them to gain motility and the ability to fertilize an ovum over a period of days to weeks. During this time, sperm are stored until ejaculation occurs. When ejaculation takes place, mature sperm travel from the epididymis through the vas deferens and ultimately mix with seminal fluid to form semen.

In contrast, the other functions mentioned in the options are associated with different parts of the reproductive or circulatory systems. For example, hormone regulation is primarily managed by the endocrine system, the production of sperm occurs in the testes, and the transportation of blood is a function of the circulatory system. The specific role of the epididymis in storing and maturing sperm before ejaculation is why it is considered the correct answer.