Cardiac physiology ventricles, pushing open the tricuspid and mitral valves. As pressure drops within the ventricles, blood flows from the major veins into the relaxed atria and from there into the ventricles. Both chambers are in diastole, the atrioventricular valves are open, and the semilunar valves remain closed. The cardiac cycle is complete. One of the simplest methods of assessing the heart's condition is to listen to it using a stethoscope. In a healthy heart, there are only two audible heart sounds, called S1 and S2. The first heart sound S1, is the sound created by the closing of the atrioventricular valves
How Many More Times "most representative cut". Mendelsohn complimented Page's guitar solo and Bonham's drumming but criticized Plant's vocals, calling them "strained and unconvincing". How Many More Times "How Many More Times" is the ninth and final track on English rock band Led Zeppelin's 1969 debut album "Led Zeppelin". The song is credited in the album liner to Jimmy Page, John Paul Jones, and John Bonham, but Robert Plant was later added to the ASCAP credits. At eight and a half minutes, "How Many More Times" is the longest song on the album. It is one of three Led Zeppelin songs on which Page