How does massaging an erect penis induce ejaculation?

[Daryle]

Main area of interaction on the male partner during make-a-baby sex is his penis. But the sperm cells are stored in the nearby testicles, surrounded by the scrotum. I'm curious about the mechanics of how the stimulation of one part causes activation of another. Also do ejaculation events start from scrotum squeezing sperm from the testicles, or is there another body part between the penis and scrotum/testicles that starts the process (after enough penile stimulation)?

 

[Connor]

Your scrotum is no where near strong enough to sqeeze sperm from the testicles. (That would be incredibly painful) The begining of the process of ejaculation begins really with the sperm leaving the testicles through the tubes from which they are produced from. It happens by chemical process. Hormone signals from one part of the body tell the sperm cells what to do and where to go.

Penile stimulation creates arousal which includes increased blood flow to the genital area. As the male gets close to climax the process of stimulation like I said causes a chain of chemical reactions with hormones signaling different cells and glans to do their job and when to do it. Thus once all put together causes ejaculation.

It's an incredibly complicated and intricate process that takes a very in depth understanding of basic human biology from a cellular level. It's not something that can be exsplained (as well as understood at the same time) in a single page discription.

-Connor