Body Fluids and Circulation Question 56
56. Doctors use stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when:
[2015 RS]
(a) Ventricular wall vibrate due to gushing in of blood from atria.
(b) Semilunar valves close down after the blood flows into vessels from ventricles.
(c) AV node receives signal from $SA$ node.
(d) AV valves open up.
Show Answer
Answer : b
Hints & Solutions
(b) The second sound heard by doctors using stethoscope occurs when semilunar valves close down after the blood flows into vessels from ventricles.
