Which statement about the autonomic nervous system is accurate?

Which statement about the autonomic nervous system is accurate?

• A. PNS = fight or flight
• B. SNS = rest and digest
• C. PNS = rest and digest; SNS = fight or flight
• D. The autonomic nervous system has no effect on digestion

Answer: (C)

Think of the autonomic nervous system as the body’s automatic regulator of organ function, keeping things in balance without conscious effort. It has two divisions that usually act in opposition: the parasympathetic division promotes rest and maintenance—especially digestion and energy conservation—while slowing the heart rate; the sympathetic division prepares the body for action—fight or flight—by increasing heart rate, directing blood to muscles, and reducing digestion. Because of this setup, the statement that the parasympathetic system is rest and digest and the sympathetic system is fight or flight is correct. The other choices mix up the roles (parasympathetic as fight or flight or sympathetic as rest and digest) or claim digestion isn’t affected by the autonomic system, which isn’t true—the parasympathetic system enhances digestion and the sympathetic system tends to inhibit it.

Think of the autonomic nervous system as the body’s automatic regulator of organ function, keeping things in balance without conscious effort. It has two divisions that usually act in opposition: the parasympathetic division promotes rest and maintenance—especially digestion and energy conservation—while slowing the heart rate; the sympathetic division prepares the body for action—fight or flight—by increasing heart rate, directing blood to muscles, and reducing digestion. Because of this setup, the statement that the parasympathetic system is rest and digest and the sympathetic system is fight or flight is correct. The other choices mix up the roles (parasympathetic as fight or flight or sympathetic as rest and digest) or claim digestion isn’t affected by the autonomic system, which isn’t true—the parasympathetic system enhances digestion and the sympathetic system tends to inhibit it.