2024-09-24 18:36:23 +00:00
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The primary roles of the digestive system are:
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- breakdown of food into nutrients
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- absorption of nutrients
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- elimination of solid waste products
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Digestion is the process of breaking down large food molecules into nutrients that the body can use
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Absorption is the uptake and removal of nutrients from the digestive tract.
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- The digestive tract is also called the gastrointestinal tract (GI), alimentary canal, or gut
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# The GI tract
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## Order
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1. Mouth
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2. Esophagus*
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3. Stomach*
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4. Small intestine (DJI)
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1. Duodenum
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2. Jejunum
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3. ileum*
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5. Large intestine
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6. Rectum
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7. Anus
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2024-09-24 18:41:23 +00:00
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## Sphincters
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Sphincters are thickened regions of circular muscle that control the flow of contents at various points in the GI tract.
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- Contracted:
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- Passageway closed
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- Flow is restricted
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- Essential for normal digestion and absorption
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There are 3 main sphincters associated with digestion:
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1. Gastroesophageal/lower esophageal/cardiac - connects the esophagus to the stomach
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2. Pyloric - connects the stomach to the duodenum (small intestine)
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3. ileocecal valve - Connects the small intestine to the large intestine
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The upper esophageal sphincter is at the top of the esophagus (not as important).
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