What is an erection

What is an Erection ? (Educational Demonstration 18+)

Original was uploaded on 2025-02-11

An erection is a physiological phenomenon in which the penis becomes firm, engorged, and enlarged. Penile erection is the result of a complex interaction of psychological, neural, vascular, and endocrine factors, and is often associated with sexual arousal, sexual attraction or libido, although erections can also be spontaneous. The shape, angle, and direction of an erection vary considerably between humans.

Physiologically, an erection is required for a male to effect penetration or sexual intercourse and is triggered by the parasympathetic division of the autonomic nervous system, causing the levels of nitric oxide to rise in the trabecular arteries and smooth muscle of the penis.