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A : The cardiac impulse which originates...

A : The cardiac impulse which originates from SA node in mammalian heart cannot spread directly from atria to ventricles
R : In mammalian heart there is no continuity between cardiac muscle fibres of atria and those of ventricles except AV bundles.

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

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The correct Answer is:
A
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Knowledge Check

  • Assertion : the cardiac impulse which originates from SA node in mammalian heart cannot spread directly from atria to ventricles. Reasoning : In mammalian heart, there is no continuity between muscle fibers of atria and those of ventricles except AV bundles.

    A
    If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
    B
    If both Assertion and Reason are true, but the Reason is not the correct explanation of the Assertion.
    C
    If Assertion is true, but Reason is false.
    D
    If both Assertion and Reason are false.

  • Assertion : The AV bundle is essential for the conduction of cardiac impulse. Reason: There is no continuity between the cardiac muscle fibers of the auricles and those of the ventricles.

    A
    If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
    B
    If both Assertion and Reason are true, but the Reason is not the correct explanation of the Assertion.
    C
    If Assertion is true, but Reason is false.
    D
    If both Assertion and Reason are false.

  • In order for the blood to flow from right ventricle to left ventricle in mammalian heart, it must flow through

    A
    Right ventricle, pulmonary arteries Lungs Pulmonary veins, Left atrium
    B
    Right ventricle, Pulmonary veins, Lungs Pulmonary arteries, Left atrium
    C
    Right ventricle, Right atrium lungs pulmonary veins Left atrium
    D
    Right ventricle , systemic aorta lungs pulmonary veins left atrium

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    Which of the following statement(s) is/are correct? I. Bundle of His originates from the SA-node. SA-node is situated in the wall of right auricle. III. Auricular contraction stimulates the AV-node. IV. AV-node sets up the cardiac impulses 72 times per minute. Choose the correct answer.

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