Final answer:
The removal of ANS input on the heart increases the heart rate.
Step-by-step explanation:
The effect of removing ANS (autonomic nervous system) input on the heart is an increase in the heart rate. The ANS consists of sympathetic and parasympathetic nerves that regulate the heart rate. The parasympathetic nerves normally predominate and slow down the heart rate, while the sympathetic nerves increase the heart rate. Without parasympathetic input, the pacemaker cells of the heart would generate a resting heart rate of about 100 beats per minute instead of the normal resting heart rate of about 72 beats per minute.