The Mouth - Saliva contains water (99.5 percent), digestive...

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The Mouth The mouth (oral cavity, buccal cavity) is where food enters the digestive tract. The following features  are found in the mouth:  The vestibule is the narrow region between the cheeks and teeth and between the lips and  teeth. The tongue defines the lower boundary of the mouth. It helps position the food during  mastication (chewing) and gathers the chewed food into a ball, or  bolus,  in preparation for  swallowing. The tongue is covered with papillae, small projections that help the tongue grip  food. Many of the papillae bear taste buds.  The palate defines the upper boundary of the mouth. The forward portion is the hard  palate, hard because bone (maxillae and palatine) makes up this portion of it. Further back  in the mouth, the soft palate consists of muscle and lacks any bone support. A conical  muscular projection, the uvula, is suspended from the rear of the soft palate.
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Unformatted text preview: Saliva contains water (99.5 percent), digestive enzymes, lysozyme (an enzyme that kills bacteria), proteins, antibodies (IgA), and various ions. Saliva lubricates the mouth, moistens food during chewing, protects the mouth against pathogens, and begins the chemical digestion of food. Chemical digestion is carried out by the digestive enzyme salivary amylase, which breaks down polysaccharides (starch) into short chains of glucose, especially the disaccharide maltose (which consists of two glucose molecules). Saliva is produced by the following glands: There are three pairs of salivary glands: the parotid (located near the masseter muscle), submandibular (located deep in the mandible), and sublingual (located under the tongue). They deliver their secretions to the mouth via ducts. Buccal glands are located in the mucosa that lines the mouth....
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This note was uploaded on 11/10/2011 for the course PT 101 taught by Professor Staff during the Spring '10 term at Texas State.

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