Question

Read the assertion and reason carefully to mark the correct option out of the options given below:
(a) If both the assertion and the reason are true and the reason is a correct explanation of the assertion
(b) If both the assertion and reason are true but the reason is not a correct explanation of the assertion
(c) If the assertion is true but the reason is false
(d) If both the assertion and reason are false
(e) If the assertion is false but reason is true
Assertion : The muscle fibres of SA node posses the lowest rhythmicity among all cardiac muscle fibres.
Reason : Due to this fact it can initiate excitory waves at the highest rate

Answer 1

Correct Answer - E
SA node and AV node are the contraction node. SA node possess the highest rhythmicity among all cardiac muscle fibres and can initiate excitory wave at highest rate.