Fimbriae (A), associated with the oviduct (IV), assist in capturing ova released from the ovary. Seminiferous tubules (B), located in the testes (II), are the site of sperm production. The acrosome (C), a cap-like structure on spermatozoa (I), contains enzymes for egg penetration during fertilization. The Graafian follicle (D), found in the ovary (III), is the mature ovarian follicle just before ovulation.