Heart sounds are generated when blood vibrates the wall of the heart due to the ______ of the valves.Multiple choice question.stretchingopeningclosing

When the first heart sound is heard, what is occuring with the heart valves?Multiple ChoiceThe semilunar valves are closing.The AV valves are opening.The semilunar valves are opening.The AV valves are closing.

What heart sound occurs with closure of AV valves?Group of answer choicesS1 (first heart sound)S2 (second heart sound)S3 (third heart sound)S4 (fourth heart sound)

The opening and closing of the heart valves is associated with ______.Multiple choice question.changes in blood oxygenationchanges in blood compositionchanges in chamber pressurestretch of tissue fibers in the pericardium

Which heart sound occurs at the beginning of isovolumetric contraction?Multiple choice question.ThirdFirstSecond

Which statement is correct with regarding to the cardiac cycle ?The pause between the end of the second heart sound and the beginning of the first heart sound coincides with ventricular diastoleDuring ventricular systole, atrioventricular valves open and semilunar valves closeFrom the atria nearly 70% of the blood flows into the ventricles during atrial systoleThe first heart sound is of shorter duration and created by the closure of the semilunar valves.