Question

Parameter not affected by sympathetic stimulation of heart?

• A. Cardiac output
• B. Stroke volume
• C. Duration of cardiac cycle
• D. Involuntary nature of cardiac musculature

Answer 1

The correct option is D Involuntary nature of cardiac musculature

The involuntary nature of cardiac muscles is the major quality that makes them contract and relax continuously without pausing or without experiencing any fatigue like the rest of the muscles of our body. The parasympathetic nervous system has effects antagonistic to those of the sympathetic nervous system. The parasympathetic stimulation oh cardiac muscles, however, cannot change the involuntary nature of the cardiac musculature.

So, the correct answer is 'Involuntary nature of cardiac musculature'.