histology tract

• innermost tunic, the mucosa, or mucous membrane, consists of three layers
• the inner mucous epithelium, which is moist stratified squamous epithelium in the mouth
• loose connective tissue called the lamina propria
• thin outer layer of smooth muscle, the muscularis mucosae.
• epithelium extends deep into the lamina propria in many places to form intestinal glands and crypts
• submucosa, a thick connective tissue layer. This tunic contains nerves, blood vessels, lymphatic vessels, and small glands
• network of nerve cells in the submucosa forms the submucosal plexus
• The next tunic is the muscularis, a muscular layer
• myenteric plexus controls the motility of the intestinal tract.
• interstitial cells form a network of pacemakers
• enteric nervous system (ENS) which is extremely important in controlling secretion and movement
• serosa or an adventitia, foreign or coming from outside. protrude into the peritoneal cavity
• three major types of enteric neurons, Enteric sensory neurons, Enteric motor neurons, Enteric interneurons
• Enteric sensory neurons, detect changes
• enteric motor neurons stimulate or inhibit smooth muscle contraction and glandular secretion
• enteric interneurons connect enteric sensory and motor neurons
• local reflexes to control activities within specific, short regions of the digestive tract
• Hirschprung disease poor intestinal motility observed in patients
• covers the organs is the visceral peritoneum
• covers the interior surface of the wall of the abdominal cavity is the parietal peritoneum
• Peritonitis is a potentially life-threatening inflammation of the peritoneal membranes
• accumulation of excess serous fluid in the peritoneal cavity, called ascites
• organs within the abdominal cavity are held in place by connective tissue sheets called mesenteries
• mesentery associated with the small intestine, sometimes called the mesentery proper
• transverse mesocolon, which extends from the transverse colon
• vermiform appendix has its own little mesentery, called the mesoappendix
• proximal end of the duodenum to the liver and diaphragm is called the lesser omentum
• mesentery extending as a fold from the greater curvature and then to the transverse colon is called the greater omentum
• omental bursa forms between the two layers of mesentery
• coronary ligament attaches the liver to the diaphragm
• falciform ligament attaches the liver to the anterior abdominal wall
• abdominal organs that have no mesenteries are referred to as retroperitoneal