01. Male reproductive anatomy
The penis is composed of paired erectile bodies. The interior of the corpus caverosum contains vascular spaces that consist of connective tissue and corporal smooth muscle.
Read02. Physiology of the erection
An erection begins with stimulation. Then impulses from the brain travelling down the spinal column and impulses from the nerves in the penis relax the smooth muscles.
Read 03. Physiology of the erection II
An erection begins with sensory and mental stimulation. Impulses from the brain and nerves in the penis relax the smooth muscles. Take a look at these cross-section images.
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04. Causes of ED
An erection is the result of a series of psychological and physical events. If a problem occurs at any step in the process, the erection may be absent, insufficient or short-lived.
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