The flight-or-fight neural response that increases heart rate and contractility is called:

• A. Parasympathetic Nervous System
• B. Sympathetic Nervous System
• C. Enteric Nervous System
• D. Somatic Nervous System

Answer: (B)

The flight-or-fight response is driven by the sympathetic nervous system. When activated, sympathetic fibers release norepinephrine onto the heart’s beta-1 receptors, which increases heart rate (chronotropy) and contractility (inotropy). The adrenal medulla also releases epinephrine into the bloodstream, further boosting these effects. This coordinated surge readies the body for quick action. In contrast, the parasympathetic system slows the heart rate via the vagus nerve, the enteric system handles gut activity, and the somatic system controls voluntary muscles, so they don’t generate the rapid cardiac activation seen with fight-or-flight.