EVERYDAY SCIENCE

Detailed explanation-1: -The sympathetic nervous system releases norepinephrine (NE) while the parasympathetic nervous system releases acetylcholine (ACh). Sympathetic stimulation increases heart rate and myocardial contractility.

Detailed explanation-2: -The sympathetic nervous system (SNS) releases the hormones (catecholamines-epinephrine and norepinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate.

Detailed explanation-3: -The sympathetic nervous system increases heart rate, whereas the parasympathetic nervous system suppresses it. Heart rate variability (HRV) can be analyzed using electrocardiography (ECG) to assess the activity of the autonomic nervous system (Kimura et al., 1996).

Detailed explanation-4: -The sympathetic nervous system (SNS) has a wide variety of cardiovascular effects, including heart-rate acceleration, increased cardiac contractility, reduced venous capacitance, and peripheral vasoconstriction.

Detailed explanation-5: -Heart, sympathetic activation causes an increased heart rate, the force of contraction, and rate of conduction, allowing for increased cardiac output to supply the body with oxygenated blood. Lungs, bronchodilation and decreased pulmonary secretions occur to allow more airflow through the lungs.