Male gonad which functions to produce sperm and testosterone; singular form of testes.
One of the pair of oval glands that produce sperm, the male reproductive cells, and the male sex hormone testosterone. Also called testes, the testicles are located in the groin in a sac of skin called the scrotum. The male hormones secreted in the testicles, including testosterone, influence male characteristics, such as facial hair and a lower voice, sexual desire, and sexual function. These secretions are known collectively as androgen hormones. Muscle fibers originating from the groin surround the testicles.
Either of the pair of male sex organs within the scrotum. It consists of the testis and its system of ducts (the vasa efferentia and epididymis).
Men have two testicles or testes which are the sexual glands. In the fetus, they develop in the abdomen, but before birth they descend into a fold or pouch of skin known as the scrotum. Each testicle consists of up to 1,000 minute tubes lined by cells from which the spermatozoa are formed. Around 4.5 million spermatozoa are produced per gram of testicle per day. These tubes communicate with one another near the centre of the testicle, and are connected by a much coiled tube, the epididymis, with the vas deferens, which enters the abdomen and passes to the base of the bladder. This duct, after joining a reservoir known as the seminal vesicle, opens, close to the duct from the other side of the body, into the urethra where it passes through the prostate gland. Owing to the convulutions of these ducts leading from the testicles to the urethra, and their indirect route, the passage from testicle to urethra is over 6 metres (20 feet) in length. In addition to producing spermotozoa, the testicle also forms the hormone testosterone which is responsible for the development of male characteristics.
One of two egg-shaped glands found inside the scrotum that produce sperm and male hormones. Also called a testis.