The digestive system part 1

is a continuous tube that extends from the mouth to the anus through the thoracic and abdominal pelvic cavities.  Organs of the GI include include the mouth, most of the pharynx, esophagus, stomach, small and large intestines. its length is 5-7 meters

teeth, tongue, saliva, liver, gallbladder, pancreas

taking food in

release of water, acid, buffers and enzymes into the lumen of the GI tract

churning and propulsion through the GI tract

mechanical and chemical break down of food

the elimination of feces from the GI tract

passage of digested products from the GI tract into the blood and lymph

the capability of the GI tract to mix and move material along its length

the brain of the gut.  it consists of 100 million neurons that extend from the esophagus to the anus. They are arranged into two plexus

is located between the longitudinal and circular smooth muscle layers of the muscularis. It mainly controls GI tract motility

the teeth cut and grind food before it is swallowed, and then smooth muscles of the stomach and small intestine churn the food.  As a result food molecules become dissolved and throughly mixed with digestive enzymes.

the large carbohydrate, lipid, protein and nucleic acid molecules in food are split into smaller molecules by hydrolysis.  Vitamins ions, cholesterol and water can be directly absorbed without this.

the inner lining of the Gi tract is a mucous membrane.  It is composed of three layers

in direct contact with the contents of the Gi tract

found in the epithelium of the mucosa they secrete hormones into the lumen

is areolar connective tissue containing many blood and lymphatic cells, which are routes by which nutrients absorbed into the GI tract reach other tissues of the body

these lymphatic nodules contain immune system cells that protect against disease.  Found in lamina propria layer

A thin layer of smooth muscle fibers found in the mucosa, throws the mucous membrane of the stomach and smooth intestine into many small folds, which increase the surface area for digestion and absorption

consists of areolar connective tissue that binds the mucosa to the muscularis.  It contains many blood and lymphatic vessels that receive absorbed food molecules.

an extensive layer of neurons found in the submucosa

found in the mouth, pharynx and esophagus contain skeletal muscle that produces voluntary swallowing. the sphincter at the end is also voluntary. The rest of the tract has smooth muscle tissue found in two layers.

found between two layers of smooth muscle tissue in the muscularis is this neuron plexus

the portions of the GI tract that are suspended in the abdominal pelvic cavity have this superficial layer.  It is a serous membrane.  It is also called the visceral peritoneum because it forms a portion of the peritoneum.

the esophagus lacks a serosa and instead only has a single layer of areolar connective tissue called this that forms the superficial layer of this organ

these neurons supply the secretory cells of the mucosal epithelium, controlling the secretions of the organs of the GI tract.

is the largest serous membrane of the body

lines the wall of the abdominal cavity

covers some of the organs in the cavity and is their serosa

the slim space containing lubricating serous fluid that is between the parietal and visceral portions of the peritoneum.

the organs that lie on the posterior abdominal wall and are covered only anteriorly by peritoneum.  They are not in the peritoneal cavity.  They include kidneys, ascending and descending colons of the large intestine, duodenum of the small intestine and pancreas

the largest peritoneal fold, drapes oves the transverse colon and coils of the small intestine like a fatty apron.  It is a double sheet that folds back on its self, giving it a total of four layers

attaches the liver to the anterior abdominal wall and diaphragm.  The liver is the only digestive organ attached to the abdominal wall

arises as an anterior fold in the serosa of the stomach and duodenum and it suspends the stomach and duodenum from the liver.  It contains the hepatic portal vein to the liver

a fan shaped fold of the peritoneum.  It binds the jejunum and ileum of the small intestine to the posterior abdominal wall.  It extends from the posterior abdominal wall to wrap around the small intestine and then returns to its origin.

two separate folds of peritoneum that bind the transverse colon and sigmoid colon of the large intestine to the posterior abdominal wall. Together with the mesentry they hold the intestines loosely in place

is formed by the cheeks, hard and soft palates and tongue