Prostate Gland Anatomy

Prostate gland is an exocrine gland that is found only in males. Exocrine glands are those glands that secrete their products, which may include chemical secretions except hormones into the duct glands. Unlike endocrine glands, the exocrine glands don't secrete the hormones or chemical secretions directly into the blood stream, instead, exocrine glands secrete their chemical secretions in the outside environment.

Anatomy and Physiology
The prostate gland, consisting of a glandular part and stroma, is located just below the urinary bladder and at the top of the penis. Its size is almost equal to that of a walnut. It surrounds the urethra, that is the tube through which urine passes from the bladder and is discharged out through the penis. It is composed of fibrous tissues and some non-striped muscles. The urethra coming from the bladder and within the prostate is called prostatic urethra. The prostatic urethra fuses with the ejaculatory ducts in the urethra. It is to be understood that passing of urine during urination process and carrying semen while ejaculation, are the two functions of the urethra, in males.

The prostate is divided on the basis of zones and lobes. The zone classification has been specifically meant for medical purposes, where the glandular functions of each part is considered to treat any complications. The anatomy is divided into four zones. The outermost part is called peripheral zone (PZ) and it consists of 70% part of the normal prostate gland in an adult man. It is in the peripheral part that most of prostate cancers occur. The central zone (CZ) is nearly 25% of the normal gland. The central zone surrounds the ejaculatory ducts and the prostate cancers in this region are more serious and in many cases they may even affect the seminal vesicles. Seminal vesicles are structures attached to the vas deferens side of the urinary bladder. Prostate gland and seminal vesicles, act as accessory sex glands and provide fluids that help in the nourishment of sperms. The third zone or the transition zone accounts for 5% of prostate volume and this region is responsible for the prostate enlargement problems. The last zone known as anterior fibro-muscular zone or stroma, doesn't contain any glandular parts but consists of muscles and tissues. Based on the different zones, the doctors are able to classify the complications related to the prostate gland. The anatomy is also majorly classified on the basis of lobes and it is divided into four parts anterior lobe, posterior lobe, lateral lobes and median lobe.'

Function
Its chief function is the secretion of an alkaline fluid that forms a part of the seminal fluid ejaculated during the male orgasm. During the male orgasm, the muscular glands present in the prostate help the alkaline fluid besides the sperm (produced in the testicles) pass into the urethra. The semen then ejaculates through the penis. The alkaline fluid that is produced in the prostate gland constitutes 25 - 30% of the volume of the semen, besides the sperms and seminal vesicle fluid. The alkalinity of the fluid plays a crucial role in increasing the life span of the sperms. How does the lifespan of sperms increase? Well, the vaginal tract of women contains acidic fluids and the alkaline fluid that is a part of the semen helps in neutralizing the effect of the vaginal tract acids and hence increases the life of sperms.

A majority of men in the older ages are susceptible to prostate problems. Enlarged prostate and prostate cancer are two common prostate complications in men. It is advisable for men above the age of 50 years to get their prostate checked once in a year, so that the prostate health is not affected by various complications.