Structures of the male reproductive system include testes, accessory glands, penis, semen, and hormones. Testes. The testes are located outside the abdominal cavity, suspended in a sac called the scrotum, which is between the thighs. Each of the two testis (singular) is surrounded by a tough fibrous connective tissue capsule. The word for the testes originated in the Greek and so named for its oval shape – orchis.