Name the following :
(a) The body part in which the testes are present in a human male.
(b) The part where the sperms are produced in the testes.
(c) The fully developed part of the ovary containing a mature egg.
(d) The accessory gland in human males whose secretion activates the sperms.
(e) The tubular knot fitting like a cap on the upper side of the testis.