NEET BIOLOGY

HUMAN PHYSIOLOGY

BODY FLUIDS AND CIRCULATION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
How do parasympathetic neural signals affect the working of the heart?
A
Reduce both heart rate & cardiac output
B
Heart rate is increased without affecting cardiac output
C
Both the heart rate & cardiac output increase
D
Heart rate decreases but cardiac output increases
Explanation: 

Detailed explanation-1: -Parasympathetic neural signals ( a component of ANS) decrease the rate of heart beat, the speed of conduction of action potential and thereby the cardiac output.

Detailed explanation-2: -The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate. Such factors as stress, caffeine, and excitement may temporarily accelerate your heart rate, while meditating or taking slow, deep breaths may help to slow your heart rate.

Detailed explanation-3: -Parasympathetic Stimulation Slows the Heart Rate by Decreasing the Slope of the Pacemaker Potential. Parasympathetic nerves to the heart originate from the vagal motor nuclei in the brainstem and travel over the vagus nerve (cranial nerve X) to the heart.

Detailed explanation-4: -So the parasympathetic neural signals decreases the heart rate whereas the sympathetic neural signals increase the heart rate.

Detailed explanation-5: -Neural signals through sympathetic nerves increases the heart rate and the parasympathetic neural signals decreases the heart rate.

There is 1 question to complete.