1 / 17

Notes: The Stomach

Notes: The Stomach. Tuesday 1-5-2010. (1) Overall Function. Break down “bolus” from esophagus. Metabolize ALL Carbohydrates. Begin Protein Metabolism. Turn “bolus” into liquid  Small Intestine. (2) The Stomach as a Chamber.

dori
Download Presentation

Notes: The Stomach

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Notes: The Stomach Tuesday 1-5-2010

  2. (1) Overall Function • Break down “bolus” from esophagus. • Metabolize ALL Carbohydrates. • Begin Protein Metabolism. • Turn “bolus” into liquid  Small Intestine

  3. (2) The Stomach as a Chamber • Stomach can contain up to 1.5L of food without pressure changes. • Feelings of discomfort come from irritants + too much food • Stomach composed of excess tissue  Folds of Tissue = Rugae • Folds allow the stomach to expand • Folds also contain secretion glands • Food sits in the stomach for 3-4 hours • Depends on Amount & Type of food

  4. (3) Contraction & Churning • Stomach composed of smooth muscle: • Contains 3 layers of muscle = STRONG • Contracts via peristalsis • Peristalsis used to Toss & Churn (not squeeze through). • Like Shake & Bake • Contractions stimulated by release of Serotonin from Rugae.

  5. (4) Release of Gastric Juice • Gastrin (hormone) released from G-Cells within Rugae: • Triggered by smell + taste of food • Triggered by increase in pH • Gastrin stimulates release of HCl = Decreasing pH: • Proteins & Carbohydrates Metabolized • Small & Large Intestine stimulated

  6. (5) Gastric Juice • HCl = Hydrochloric Acid • Pepsin = Enzyme = Breaks down protein • Rennin = Enzyme = Breaks down protein • Muccin = Mucus = Lubricate Food Mass

  7. (6) Protein Metabolism • Proteins take a lot of Gastric Juice to Metabolize. • Breaking Down Proteins releases H+ ions. • Decreases pH of stomach. • G-Cells stop releasing gastrin  HCl stopped.

  8. (7) Exiting the Stomach • The mass leaving the stomach is called “Chyme”: • Mostly liquid  Liquids leave first! • Solids are left behind until broken down • Approximately 3mL of food leaves at one time…. • Food Exits the Pyloric Sphincter • Chyme dumped into Small Intestine

More Related