N.+Digestion

DIGESTION There is basically a complex circus going on in our body that allows our body to digest and breakdown everything that we consume. Digestion occurs in the lumen of the GI tract and is catalyzed by specific enzymes. The organs and main areas of focus in our body that play a key role in digestion are our mouth, stomach, small intestine, large intenstine, liver, gallbladder, and pancreas. That is quite the team!

__I. The Layers (tunics) of the GI Tract__*Consist of the mucosa, submucosa, muscularis and serosa in order from the inside to outward *The mucosa is made of simple columnar epithelium, a layer of connective tissue which is called the lamina propria and a muscularis mucosae which is a thin layer of smooth muscle *The submucosa is made up of connective tissue and contains the submuscosal plexus *The muscularis is made up of layers of smooth muscle *Finally, the serosa is made up of connective tissue that is conceled by the viscral peritoneum



II. Mouth to Stomach *Peristaltic waves of contraction are responsible for pushing food through the lower esophageal sphincter into the stomach during digestion *Our stomach’s lining has folds called rugae and they have gastric pits that lead to gastric glands *The parietal cells of our gastric glands secrete HCl and the chief cells secrete pepsinogen, later converted into pepsin once it is in an acidic environment of gastric juices *The most important part to note of our stomach is the secretion of intrinsic factor, which is needed for our body to absorb vitamin B12 in our intestine media type="youtube" key="3825vuwfCBo" height="314" width="382" align="center"

III. Small and Large Intestines *The small intestine is divided into the duodenum, jejunum, and ileum *The small intestines show two major styles of movement which are segmentation and also peristalsis *The large intestines is divided up into the colon, cecum, rectum, and anal cavity *Bulges in the walls of the large intestines are called haustra *The large intestines major responsibility in digestion is to absorb about 90% of water and electrolytes *Also, defecation occurs when the sphincters relax and contract with muscles to raise the rectal pressure



APPLICATION: Working in the pharmacy hospital this section really rings home! The first thing digestion makes me think of is our end result of defecation. What goes in, obviously not used to fuel our body must come out! How lovely! We dispense so much drugs for issues with stools they kind of fall into a few classes depending on the severity of the case. A few examples are stool softeners and laxatives for those who are constipated and cannot relieve themselves. Senna and docusate sodium are prescribed quite often. Special diets, stress, lifestyle, disease states and even pain medication can affect your digestive system responses. There are also another class for this same area of consideration which would include drugs like loperamide (Imodium) and bismuth, which are anti-diarrhea medication for frequent and soft stools. Oh lovely but, it is a part of life!



Essential Questions: Two key organs that aid in digestion are the large intestine and the stomach. In the large intestines the structure makes me automatically think of a manufacturing process line because though there is not a lot of digestive function the chime does go through a process of other things like an assembly line. Not only does the large intestine help frame the small intestine, which is similar in shape but, it contains haustra which look like bulges or pouches that would aid in the organ being able to absorb water and electrolytes. The stomach’s shape is of a “J” and its descending shape is perfect for it breaking down our food in digestion. It reminds me of a funnel and allows for our food to be exposed to gastric juices and glands to be broken down from hormones as it continues to pass through our body.
 * || Location of Digestion || Aiding Enzymes || How Absorbed || How Body Uses It ||
 * ** Carboyhdrates ** || Mouth & Duodenum || Salivary amylase, Pancreatic amalyse, brush border || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Becomes monosaccharides and secreted in blood || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Source of Energy ||
 * ** Protein ** || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Duodenum & Jejunum || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Endopeptidases, brush border Aminopeptidase || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Converted into free amino acids secreted in blood || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Rebuilds and Repairs ||
 * ** Fat ** || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Duodenum,S.Intestines || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Pancreatic Lipase, Phospholipase A || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Form chylomicrons ans secreted into central lacteals || <span style="color: black; display: block; line-height: normal; margin-bottom: 0.0001pt; text-align: center;">Source of Building Blocks ||

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