What jobs do the external sex organs do?
The external male sex organs include the penis and the scrotum. The main purpose of the external sex organs is to allow for sexual intercourse and sexual pleasure. The structure of the penis is similar to that of the female clitoris, apart from the fact that the clitoris is mostly inside the body. During the time in the womb, they both develop from the same organ.
The penis can carry and release the man’s sperm into a woman's vagina. The round glans (head) of the penis is located at the tip of the longer shaft of the penis. It is covered with a mucous membrane. The movable foreskin (partially) covers the head of the penis. In some men, the foreskin has been shortened or removed in a medical procedure known as circumcision.
A tube called the urethra runs through the inside of the penis. Urine leaves the body through the urethra, and so does semen (the fluid that carries sperm) during ejaculation. The shaft and the head of the penis contain erectile tissues called corpora cavernosa. These tissues are like sponges. During sexual arousal, blood builds up in the corpora cavernosa until they are full and firm. This allows the penis to become erect and stiff (erection). In most men, it also becomes longer and thicker.
The scrotum is a bag of skin that surrounds the testicles, the epididymis and the start of the vas deferens.
The head of the penis and the skin on the penis, scrotum and the surrounding area contain a dense network of nerve fibers. This makes the external sex organs very sensitive. As a result, touching and rubbing this area can cause sexual arousal and increased pleasure that may lead to orgasm and trigger ejaculation.