Penis Anatomy - Know Your Penis

To understand how penis enlargement works it helps to know a little bit about the anatomy of the penis.

The penis is mainly comprised of four different sections. The main two are called the Corpus Cavernosa, these two identical chambers run the whole length of the penis. When aroused the brain releases hormones causing the soft, spongy tissue to engorge with blood to create an erection. The other section is the Corpus Spongiosum, this chamber is designed to keep the urethra from being pinched shut by the Corpus Cavernosa during an erection. The other is the head of the penis known as the glans penis.

The size of an erection depends mainly upon two factors, the flow of blood to the penis and the amount blood the penis can hold. Therefore the size of an erection is limited to the amount of blood the penis can hold. When you perform penis enlargement exercises or use penis stretching devices, the forces exerted upon the penis over time cause the cells of the Corpus Cavernosa to grow and hold more blood. This allows the penis to grow in both length and girth.

Anatomy of the male reproductive system

Notice in the diagram above how far the penis extends into the abdomen.

Transverse diagram of the penis

You can see in the diagram above the Corpus cavernosa, the spongy tissue that is filled with blood during an erection. Most penis enlargement methods focus on increasing the blood holding capacity of these two chambers. - Natural Penis Enlargement Exercises For Bigger, Harder and Longer Lasting Erections
Glossary of penis anatomy terms

We have compiled a list of terms commonly used to help you when referring to the male anatomy.

Corpus Cavernosum

These are two areas of spongy erectile tissue along the shaft of penis that engorge with blood causing an erection. (plural: Corpora Cavernosa)

Corpus Spongiosum

The function of the Corpus Spongiosum is to prevent the urethra from pinching closed during an erection. To do this the Corpus spongiosum remains soft and pliable while the Corpora Cavernosa is engorged with blood. This allows for the unrestricted flow of semen. (Plural: Corpora Spongiosa)


The epididymis is a storage and maturation place for sperm after they are produced by the testes. They are located on each testicle and connect to the vas deferens.


The foreskin is a retractable layer of skin that covers the head of the penis (glans penis) when not erect.

Glans Penis

Is the tip of the penis also referred to as the head or knob. It is usually wholly or partially covered by the foreskin except when the penis is erect or the man is circumcised.


A method of penis enlargement exercise. It involves gripping the penis with the thumb and index finger and squeezing the blood from the base of the penis to the glans. This technique causes the tissue of the penis to grow to accommodate the increased blood flow.


The Kegel or PC Squeeze is another enlargement exercise technique in which the person continually flexes the pubococcygeus muscle. This is the muscle you use to control ejaculations and urination.


The prostate is a gland the size of walnut located in the abdomen just below the bladder. The role of the prostate is to produce and store a clear liquid that makes up 10-30% of the semenal fluid.

Pubococcygeus muscle

Commonly referred to as the PC muscle. This muscle can be located by stopping the flow of urine, the muscle you feel squeezing is the PC muscle. This muscle can be strengthened by continually squeezing it a couple of hundred times a day.


A protruding sack of skin and muscle containing the testes. It is located between the penis and the anus and is designed to regulate the temperature of the testes. The temperature is controlled by moving the testicles closer to the abdomen when it is cold, and away when hot.


Semen is the fluid used to deliver the sperm of the male into the uterus of the woman. Semen is made up of sperm cells and other nutrient enriched fluids that help protect the sperm when inside the woman's reproductive system. Most semen is white in color, but gray or even yellowish semen can be normal as well. The process of expelling semen is called ejaculation.

Seminal Vesicle

About 70% of the seminal fluid in humans originates from the seminal vesicles. The fluids produced from this gland contain proteins and enzymes that provide nutrients for the sperm.


The Testes serve two main functions these are the production of sperm and male sex hormones such as testosterone. It is very common for one testicle to hang lower then the other.


A procedure for manually pulling a part of the body for beneficial effect.

Traction uses weights and/or pulleys to put tension on bones, muscles and other tissue. Treatment involves applying the tension over a certain period of time, this can range from days to months.


The Urethra is an 20 cm long tube that extends from the bladder to the tip of the penis. The male urethra has two functions: to expel urine from the bladder during urination and to carry semen during ejaculation.

Vas Deferens

During ejaculation these two 30 cm long muscular tubes contract thus propelling the semen forward from the epididymis. The sperm are transferred from the ductus deferens into the urethra.

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