Gastrointestinal Anatomy and Physiology Quiz

The preganglionic fiber enters the sympathetic trunk, passes through it, and then enters the greater splanchnic nerve.

The greater splanchnic nerve passes through the crura of the diaphragm and enters the celiac ganglion, where the preganglionic fiber synapses with the postganglionic neuron.

The parasympathetic innervation to the abdominal organs comes from the vagus nerves, which enter the abdomen as the anterior and posterior vagal trunks and send branches to the abdominal prevertebral plexus. These branches contain preganglionic parasympathetic fibers and visceral afferent fibers, which are distributed along the branches of the abdominal aorta.

The enteric nervous system controls the activities of the gastrointestinal tract. The sympathetic system can modify these activities, as input from the sympathetic system may influence the functions of the gastrointestinal tract that are controlled by the enteric nervous system.

The white ramus communicans is the pathway by which the preganglionic fiber leaves the anterior ramus of the spinal nerve and connects to the sympathetic trunk, allowing the sympathetic innervation to reach the target organs.

The celiac ganglion is the location where the preganglionic fiber from the greater splanchnic nerve synapses with the postganglionic neuron, allowing the sympathetic innervation to be transmitted to the target organs of the gastrointestinal tract.

Visceral afferents that pass through sympathetic trunks and splanchnic nerves

After passing posteriorly to the root of the lungs, the right and left vagus nerves approach the esophagus. As they reach the esophagus, each nerve divides into several branches that spread over the esophagus, forming the esophageal plexus. Just above the diaphragm, the fibers converge to form the anterior and posterior vagal trunks.

The anterior and posterior vagal trunks, esophageal branches of the left gastric artery and vein, and a few lymphatic vessels pass through the esophageal hiatus along with the esophagus.

The parasympathetic innervation is provided by the vagus nerves, which form the esophageal plexus and vagal trunks. The sympathetic innervation is relayed through the sympathetic trunks and splanchnic nerves, which are involved in detecting esophageal pain.

The text does not mention the white ramus communicans or its role in esophageal innervation.

The text does not provide any information about the enteric nervous system or its role in esophageal innervation.

Preganglionic sympathetic fibers originate from the T6 level of the spinal cord, enter the anterior root, and then synapse in the celiac ganglion. Postganglionic fibers from the celiac ganglion travel along the greater splanchnic nerve to innervate the stomach.

The white ramus communicans carries the preganglionic sympathetic fibers from the spinal cord to the sympathetic trunk, where they synapse in the celiac ganglion before innervating the stomach.

The parasympathetic innervation to the stomach is preganglionic, with the vagus nerve carrying fibers directly from the brainstem to synapse with postganglionic neurons in the myenteric and submucosal plexuses within the stomach wall.

The greater splanchnic nerve carries the postganglionic sympathetic fibers from the celiac ganglion to innervate the stomach and other abdominal organs.

The enteric nervous system is a local neuronal circuit within the wall of the stomach, consisting of the myenteric and submucosal plexuses. It regulates gastric secretions, blood flow, and smooth muscle contractions (peristalsis), coordinating numerous gastrointestinal activities.

Although generally independent, the enteric nervous system receives input from postganglionic sympathetic fibers and preganglionic parasympathetic fibers that modulate its activities. This allows the CNS to influence and modify gastric functions.