Final answer:
The removal of the testis and epididymis is a part of an orchiectomy, which is different from a vasectomy where only a section of the vas deferens is removed to prevent ejaculation of sperm. After a vasectomy, sperm remain in the tail of the epididymis.
Step-by-step explanation:
The procedure that involves the removal of only the testis and the epididymis is not specifically named in the question, but it is a part of the treatment for conditions like testicular cancer and is different from a vasectomy which is a form of surgical sterilization. In the case of testicular cancer, removal of the affected testis, known as an orchiectomy, may be required. During a vasectomy, only a section of the vas deferens is removed, which prevents the ejaculation of sperm by blocking their path. If sperm do not exit through the vas deferens, they remain in the epididymis, specifically in the tail of the epididymis where mature sperm are stored until ejaculation.