Question

How is cardiac activity regulated????

Answer 1

Answer:

Due to muscle contraction of cardiac muscles which are involuntary muscle present in heart.

Answer 2

Answer:

Cardiac activity is regulated by 2 basic neuronal signals :

1. Cardiac activity is decreased by vagal nerve stimulation ( parasympathetic outflow)

2. Cardiac activity is increased by sympathetic outflow.

Parasympathetic outflow meditated by vagus nerve leads to decrease in heart rate, cardiac contractility, decrease in cardiac output. It also increases nodal delay.

Sympathetic outflow is mediated by sympathetic stimulation ( thoraco-lumbar region) . It leads to increase in heart rate , cardiac contractility .

Parasympathetic stimulation happens only to the atria.

Sympathetic stimulation happens to both Atria and ventricles.