Graves Diease
1. Our digestive system provides the body a means to transfer nutrition from the external environment into the cellular level in order to sustain life. Salivary glands, controlled by the autonomic nervous system, are located in the oral cavity. Its main role is to secrete saliva in the oral cavity. There are three pairs of salivary glands. Parotoid savary gland lies under the skin on each side of the mandible. These glands secrete amylase, an enzyme that breaks down starches. The parotoid duct implies empties into the vestibule at the level of the second upper molar. The sublingual duct is (located under the tongue) between the mucus membrane of the floor of the mouth and the submandibular duct is located in the floor of the mouth. Both the sublingual and submandibular glands secrete saliva that contains more buffers and mucus. Saliva consists of 99.4% water, mucines and an assortments ions, buffers, and waste products and enzymes. The mucines absorbs water and form the mucus. During meal time, the saliva lubricates the mouth along with dissolved chemicals that stimulates the taste buds. The mucus coats the food, and reduces friction making swallowing easier. The continuous flow of saliva also flushes and cleans the oral surfaces while controlling oral bacteria through salivary antibodies. The pH of saliva during meal time rises from slightly acidic pH 6.7 to more alkaline pH 7.5. Radiation and emotional distress can cause a reduction of salivary secretions. This then can create an unhealthy oral cavity environment due to increased bacteria population. Over time, the complications caused by the decreased salivary secretions are infection and erosion of the teeth and gums. The stomach is another component of the digestive system which is located within the left upper quadrant of the abdominal cavity. It is a muscular J-shaped organ that is positioned inferior of the esophagus and superior to the small intestines. There are four primary functions the stomach has to
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