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A : First phase of ventricular filling i...

A : First phase of ventricular filling is rapid and causes `3^(rd)` sound of heart.
R : It is because of auricular systole.

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).

C

If Assertion is true statement but Reason is false, then mark (3).

D

If both Assertion and Reason are false statements, then mark (4).

Text Solution

Verified by Experts

The correct Answer is:
C
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Assertion : First heart sound (LUBB) is produced at the beginning fo ventricular systole stage. Reason : During ventricular systole semilunar valves are closed.

Indicate whether the following statements are true of false : (a) Both auricles of amphibian heart open into the same ventricle. (b) Prawn's heart carries only oxygenated blood. (c ) Purkinje fibres are nerve fibres supplying the ventricular muscles. (d) The first heart sound results from a closure of semilunar valves. (e ) The vagus nerve reduces the heart rate. (f) The A-V node normally initiates the cardiac impulse. (g) Semilunar valves open during the ventricular diastole.

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