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Question
When are the sounds "LUBB" and "DUP" produced respectively during heart beat?
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Solution
- The first sound LUBB, is produced when the atrioventricular valves, i.e. tricuspid and bicuspid, valves close at the start of ventricular systole.
- The second sound, DUBB, is produced at the beginning of ventricular diastole when the pulmonary and aortic semilunar valves close.
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