In the heart: a. excitation begins in the sinoatrial node b. excitation of the ventricle begins at the apex and spread to the base c. depolarization occurs from epicardium to endocardium d. all above

In the heart:
a. excitation begins in the sinoatrial node
b. excitation of the ventricle begins at the apex and spread to the base
c. depolarization occurs from epicardium to endocardium
d. all above
by

1 Answer

Answer :

all above
by

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