The function of the prostate is to secrete a fluid which contributes to the volume of the semen. This prostatic fluid is slightly alkaline, milky or white in appearance, and in humans usually constitutes roughly 30% of the volume of semen, the other 70% being spermatozoa and seminal vesicle fluid.
The prostate gland is a male reproductive organ whose main function is to secrete prostate fluid, one of the components of semen.
The muscles of the prostate gland also help propel this seminal fluid into the urethra during ejaculation . The prostate is a muscular gland that weighs about three-fourths of an ounce (20 grams) about the size of a small apricot. It surrounds the urethra just beneath the bladder .This diagram with labels depicts and explains the details of Prostate Function.