It is the germinal gland, two male gonads that produce sperm and the sex hormones testosterone, forming the most important part of the male reproductive system. They are located under the penis, between the two muscles, in front of the perineum, being surrounded by a set of bag-shaped covers, called scrotum.

The two gonads do not occupy the same level, since in most men the left testicle goes down more than the right one, they are suspended from the lower end by the spermatic condom and they lack adherence on most of their surface, so they are mobile in all directions, contracting and ascending towards the inguinal ring.

The testicles develop inside the abdominal cavity, on each side of the kidneys, which leave the third month of fetal development and descend dragging the bags that surround them, this process is done through the inguinal canal. There are two but only one can be present, incomplete descent is called cryptorchidism and when both testicles are missing it is called anorchidism.

The size varies from a child to hungry adult, in the infant the measure is 3 centimeters in length, in puberty they grow to reach about 18 centimeters in length and about 3 centimeters in width; conserving this size for the rest of life but in old age a possible atrophy or a slight increase in size is perceived due to the consumption of steroids, but the safest cause is a hydrocele, that is, a liquid accumulation of the serous tunic of the testicle.

They have a bluish white color, sometimes red when they are full of blood, due to this coloration to the bag that surrounds them. It has an ovoid shape, flattened in the transverse direction, with a hard consistency, elastic due to the fibrous layer that surrounds them. Its structure is composed of: The albuginea; which is a fibrous layer of connective tissue that surrounds the testis and the epididymis. The seminiferous ducts; They are the sperm producers. The excretory ducts of the sperm; They are where the semen passes when leaving the seminiferous duct, these are the straight ducts, Haller’s Red duct and the efferent cones.