The atrioventricular valve is one of the four valves present in the heart the function of which is to stop the back flow of the blood from the ventricles to the atrium.
These valve opens and closes in response to the change in the pressure of the blood in atrium and ventricles. The valve opens when blood is pumped form the atrium to ventricles which causes the papillary muscles to relax while the valve closes when the ventricles push the blood to the arteries. This causes the papillary muscle to contract which causes the chordate tendineae to create tension ad close the valve.
Helium does not react with any other substances, thus the substance’s internal structure is never greatly affected and thus helium cannot have any chemical properties.
