Answer:
The gastrointestinal (GI) tract has a plexus in the muscles and nerves in the mucosa to facilitate the coordinated movement of food and waste through the digestive system and regulate the secretions and absorption of nutrients. The muscular layer of the GI tract contains a plexus of nerves called the myenteric plexus, which controls the contractions of the smooth muscle in the wall of the GI tract, enabling peristalsis and segmentation movements. The nerves in the mucosa layer, known as the submucosal plexus, regulate the secretions and absorptions in the lining of the GI tract.
In Hirschsprung's disease, there is a congenital absence of ganglion cells in the myenteric plexus, causing a functional obstruction in the colon due to the lack of muscle contractions. As a result, the colon becomes dilated, leading to constipation, abdominal distension, and discomfort. The symptom of this disease depends on the extent of the affected area of the colon, and it may vary from mild constipation to severe bowel obstruction, which may require surgery to remove the affected segment of the colon.
In summary, the myenteric plexus in the muscular layer of the GI tract and the nerves in the mucosa layer work together to coordinate and regulate the digestive system's movements, secretions, and absorptions. The lack of the myenteric plexus in Hirschsprung's disease results in a functional obstruction in the colon and can cause severe constipation and other complications.
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