Erection

Category B - full version without watermark 720x576 (check terms and conditions at www.teledesign.de) The embed version with watermark is free of charge. Erection is the result of complex interaction of a psychological, neural, vascular and endocrine factors which stimulate the parasympathetic division of the autonomic nervous system with minimal input from the central nervous system. Parasympathetic branches extend from the sacral plexus into the arteries supplying the erectile tissue; The arteries dilate, filling the corpora spongiosum and cavernosa with blood.