Cardiac Innervation

Question 1

In basal condition, in the SA node, parasympathetic (______ tone) is more than the sympathetic tone so, normally the _______ is the function of the vagal tone

Answer 1

vagal tone, heart rate

Question 2

The ________ muscle is predominantly supplied by the sympathetic fibers and the parasympathetic innervation of ventricle is sparse.

Therefore, ________as the function of myocardial contractility is greatly influenced by the ________ tone.

Answer 2

ventricular
stroke volume, sympathetic

Question 3

Parasympathetic Innervation

The cardiac parasympathetic (Vagal) fibers originate from the three vagal nuclei present in the _______ ______ (nucleus tractus solitarius, the dorsal motor nucleus of vagus and the nucleus ambiguous).

Answer 3

medulla oblongata

Question 4

Parasympathetic Innervation

The right vagus mainly innervates _________ and _________ therefore,
stimulation of right vagus strongly ______ heart rate.

The left vagus predominantly innervates the ________, ________ and ________ therefore, stimulation of left vagus ______ or ______ AV nodal conduction.

Answer 4

right atrium, SA node, inhibits;
left atrium, AV node and the bundle of His; slows or blocks