Which of the following is associated with a decrease in cardiac output?

When the normal heart of a man is injected with a physiological concentration of adrenaline, it shows:

What is the effect on the heart rate if the parasympathetic nerve is cut in a rabbit?

Read the following statements:
$I$ - Increased heart rate.
$II$ - Increased ventricular contraction force.
$III$ - Decreased cardiac efficiency.
$IV$ - Increased cardiac efficiency.
$V$ - Decreased heart rate.
$VI$ - Decreased conduction speed of action potential.
Categorize the given statements into Sympathetic and Parasympathetic nervous systems.
Sympathetic Nervous System $\quad$ Parasympathetic Nervous System

Heart beats are accelerated by

How is the regulation of cardiac activity performed?