Sympathetic fibers leave the spinal cord in the

a) thoracolumbar region, and the postganglionic fibers secrete acetylcholine
b) craniosacral region, and the postganglionic fibers secrete acetylcholine
c) thoracolumbar region, and the postganglionic fibers secrete norepinephrine
d) craniosacral regions, and the postganglionic fibers secrete norepinephrine

The correct answer is: C) thoracolumbar region, and the postganglionic fibers secrete norepinephrine

The pathway of autonomic nervous system (sympathetic and parasympathetic) involves two:

                       1. Preganglionic neuron - from CNS (spinal cord or brain) to the autonomic ganglion, all of these fibers release acetylcholine (Ach)

                       2. Postganglionic neuron - from the autonomic ganglion to the cells of the effector organ, parasympathetic postganglionic fibers release acetylcholine while sympathetic postganglionic fibers release norepinephrine.

explanation: