The heart's normal activities are regulated:

Cardiac activities of the heart are regulated by:
$A.$ Nodal tissue
$B.$ $A$ special neural centre in the medulla oblongata
$C.$ Adrenal medullary hormones
$D.$ Adrenal cortical hormones
Choose the correct answer from the options given below:

What happens to the heart rate if the parasympathetic nerve of a rabbit is cut?

Heart beat is accelerated by

The strength of ventricular contraction increases when $SAN$ is stimulated by

Heart is innervated by