Which statement correctly describes the parasympathetic division?

Which statement correctly describes the parasympathetic division?

• A. Short preganglionic fiber
• B. Long preganglionic fiber
• C. Short postganglionic fiber
• D. Long postganglionic fiber

Answer: (B)

The main idea is how the autonomic divisions are built along nerve lengths. In the parasympathetic division, the nerve fibers are organized so the preganglionic neurons travel a long distance from the brainstem or sacral spinal cord to ganglia that are near or inside the target organs, and then the postganglionic fibers are short to reach the effector tissues. So describing the parasympathetic division as having long preganglionic fibers correctly reflects this setup, with the axons of the preganglionic neurons reaching near the organ before synapsing. The postganglionic fibers being short is also true, since the ganglia sit close to the target, but the defining feature highlighted here is the length of the preganglionic fiber. Short preganglionic fibers would align with the sympathetic division, and long postganglionic fibers would not describe the parasympathetic pattern.

The main idea is how the autonomic divisions are built along nerve lengths. In the parasympathetic division, the nerve fibers are organized so the preganglionic neurons travel a long distance from the brainstem or sacral spinal cord to ganglia that are near or inside the target organs, and then the postganglionic fibers are short to reach the effector tissues. So describing the parasympathetic division as having long preganglionic fibers correctly reflects this setup, with the axons of the preganglionic neurons reaching near the organ before synapsing. The postganglionic fibers being short is also true, since the ganglia sit close to the target, but the defining feature highlighted here is the length of the preganglionic fiber. Short preganglionic fibers would align with the sympathetic division, and long postganglionic fibers would not describe the parasympathetic pattern.