The vas deferens is part of the male reproductive system. It is a long, muscular tube that travels from the epididymis into the pelvic cavity, to just behind the bladder. Testicle or testis is the male reproductive gland in all animals, including humans. The main function of the testis is producing and storing sperm. The scrotum is the small, muscular sac that contains and protects the testicles, blood vessels, and part of the spermatic cord whereas the ovary is an organ found in the female reproductive system that produces anovum.