Mechanism of erection


This mechanism is dependent on the ability of the spongy tissue (corpora cavernosa) to become engorged with blood, usually arterial blood. This is caused by the contraction of the ischiocavernosus which assists the closure of the drainage pathway of the arteries. Also, it is believed there is a concomitant venoconstriction which helps to keep blood within the spongy tissues of the penis. This mechanism is released after the arousal has passed so that the organ becomes flaccid again. It is only in man amongst all mammals that a bone of the penis does not exist as a form of platform for the erectile mechanism of the organ. This bone is called os penis.

The penis is also responsible for the second stage of ejaculation which involves the emptying of the urethra by the assistance of the bulbospongiosus.

This mechanism is also the same for the clitoris.

Inflation and deflation of penile implant

Penis and scotum Dissected penis Parts of penis Perineum and scrotum from behind Scrotum from behind

Circumcised  penis Uncircumcised penis anatomy Structure of penis Fresh penis Variations





Gross anatomy
Lymphatic drainage
Organ integration
Clinical anatomy





Chemical Pathology

Anatomical Pathology






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