SSC MTS EXAM

Detailed explanation-1: -At this time, semilunar valves are open, and both the AV valves (bicuspid-tricuspid valves) are closed. The closing of the AV valves during the ventricular systole produces the first heart sound called “LUB".

Detailed explanation-2: -Normal heart sounds come in pairs. The sounds are often described as a constant “lub-dub, lub-dub.” The first “lub-dub” is the sound of the mitral and tricuspid valves closing. The second “lub-dub” is the sound of the aortic and pulmonary valves closing soon after.

Detailed explanation-3: -During each cardiac cycle, two prominent sounds are produced, which can be easily heard through a stethoscope. The first heart sound (lubb) is associated with the closure of the tricuspid and bicuspid valves, whereas the second heart sound (dubb) is associated with the closure of the semilunar valves.