Final answer:
The preganglionic fibers of the sympathetic division originate from the lateral horn of the thoracolumbar spinal cord and travel to either the sympathetic chain ganglia or the collateral ganglia in the thoracic cavity. These fibers release acetylcholine to activate the next neuron in the pathway, which then extends to various target organs.
Step-by-step explanation:
The preganglionic fibers in the sympathetic division of the autonomic nervous system originate in the lateral horn of the thoracolumbar spinal cord, specifically from the mid-thoracic to lower thoracic region.
These fibers then extend out of the spinal cord and travel either to the sympathetic chain ganglia located on either side of the vertebral column or to collateral ganglia, which are found anterior to the vertebral column, particularly in the thoracic cavity.
In the sympathetic system, the preganglionic fibers release acetylcholine (ACh), which excites the ganglionic neuron via the nicotine receptor.
The corresponding postganglionic fibers, which project from the ganglia, then extend to various target effectors throughout the body, where they typically release norepinephrine to cause a corresponding change in the physiology of the organ systems influenced by the sympathetic response.