Lab Report 3_revised

Lab Report 3_revised - Carly Kruchten-Sheridan Graham...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Carly Kruchten-Sheridan Thursday 9/21/06 Graham Barnett Poev Touch 1) a) How does an erection occur? An erection starts by external stimuli. This is usually from touch or sight sensory. The brain senses this stimulation and sends out the parasympathetic neurotransmitter acetylcholine (Ach) which travels down to endothelial cells within the penis and causes the release of nitrous oxide (NO) . NO is a powerful dilator which travels from the endothelium to the smooth muscle cells within the penis. It stimulates the production of cyclic GMP (cGMP) through guan y late cyclase. Cyclic GMP affects myosin, a component of smooth muscle, thus causing it to relax. This relaxation and dilation allows blood to fill the corpera cavernosa, a tissue within the penis that can become engorged with blood. The erection is maintained by the veno-occlusive mechanism. Blood is allowed to flow into the penis, but the tunica albuginea works to keep the blood from leaving. In a healthy man this erection can be sustained. b) What basic anatomical sites in the penis are involved? Corpera cavernosa are two chambers filled with a porous muscle tissue that runs along the upper side of the penis. This anatomical site fills with blood and creates an erection. Tunica albuginea is the membrane that surrounds the corpora cavernosa , it functions to sustain erections by cutting off the venus outflow of blood. The cavemosal artery is the artery that supplies blood into the penis. The deep dorsal vein is the route that is outward route for blood to leave the penis, this outflow of blood is squeezed off in order to sustain a normal erection. c) Are contractile or relaxing vascular events involved?
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 3

Lab Report 3_revised - Carly Kruchten-Sheridan Graham...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online