Case Study: Digestive Study Pud

1. The epigastric region is the upper abdomen between the bottom of the chest/ribcage and the bellybutton. The main gastrointestinal organs associated with digestion there are the stomach and first part of the small bowel (duodenum). The transverse colon also runs across the epigastric region. The liver, gallbladder, bile ducts, and pancreas are also located there and assist in digestion.

2. XII Hypoglossal nerve. Mainly Motor Medulla Hypoglossal nucleus provides motor innervation to the muscles of the tongue (except for the palatoglossus, which is innervated by the vagus) and other glossal muscles. Important for swallowing (bolus formation) and speech articulation. Located in hypoglossal canal. It controls food manipulation and swallowing. It is part of the parasympathetic nervous system.

3.

Mucosa: (not bold) moist epithelial layer that lines the lumen of the alimentary canal

-Secretion of mucus

-Absorption of the end products of digestion

-Protection against infectious disease

Submucosa - dense connective tissue containing elastic fibers, blood and lymphatic vessels, lymphoid follicles, and nerves

Muscularis externa - responsible for segmentation and peristalsis

Serosa - the protective visceral peritoneum

-Replaced by the fibrous adventitia in the esophagus

Enteric Nervous System/ Intrinsic Nerve Plexuses: Composed of two major intrinsic nerve plexuses:

Submucosal nerve plexus -regulates glands and smooth muscle in the mucosa

Myenteric nerve plexus –Major nerve supply that controls GI tract motility

4. A layer of smooth muscle cells produces local movements of mucosa. In the small intestine, this muscle layer’s tone throws the mucosa into a series of small folds that immensely increases its surface area. Except in the mouth, esophagus, and anus where it’s stratified squamous, the epithelium of mucosa is a simple columnar epithelium rich in mucus-secreting cells. The mucus it produces protects certain digestive organs from being digested by...