question_answer 25)

  The second heart sound (dubb) is associated with the closure of (a)tricuspid valve             (b) semilunar valve         (c) bicuspid valve             (d) tricuspid and bicuspid valve

Answer:

                  (b)During each cardiac cycle two prominent sounds are produced which can be easily heard through a stethoscope.                 Semi lunar value- The second sound of the heart is high pitched ?DUB? It is caused by vibrations associated with closure of aortic and pulmonary valves. It lasts for an about 0.12 seconds with the frequency of 50 Hz, while tricuspid value, bicuspid value and both the value together are associates with first heart (i.e., lubb).