Digestive system (gastrointestinal, GI tract)

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Digestive system (gastrointestinal, GI tract)

• Anatomy
• Mouth (oral cavity)
• teeth, tongue, salivary glands
• Throat
• pharynx, epiglottis ( part of the larynx
  that closes off the trachea to lungs)

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Digestive system (gastrointestinal, GI tract)

• Anatomy Mouth
• Throat
• Esophagus tube that connects pharynx to the
  stomach (about 10 in.)
• Stomach
• Small intestine
• large intestine, colon
• rectum
• anus

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Digestive system (gastrointestinal, GI tract)

• ingestion food entering the mouth
• chewingmastication or crushing food
• digestion chemical breakdown of foods
• secretion acids, buffers, enzymes and H2O
  aids in breakdown of food
• absorption broken down food is absorbed into
  the blood stream and lymph system
• excretion waste products are eliminated from
  the body

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Digestive system (gastrointestinal, GI tract)

• Oral cavity
• Teeth enamel-hardest substance in the body
• 20 baby (deciduous) 32 adult w/wisdom, 8
  Incisors, 4 cuspid, 8 premolars 12 molars (3rd
  molar wisdom)
• tongue (aids in mastication)
• salivary glands 3 pairs

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Digestive system (gastrointestinal, GI tract)
Stomach located on the left side of abdominal
cavity, under the diaphragm and covered almost
completely by the liver approximately 10
inches long, diameter varies depending on the
amount ingested, can expand due to
folds temporary holding area for food, secrets
gastric acid enzymes
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Digestive system (gastrointestinal, GI tract)
Stomach Regulates the rate, partially digested
food enters the small intestine absorbs small
amounts of water and other substances-very
limited takes about 4 hours to empty after a
meal liquids and carbohydrates pass through
quickly, protein a little more time, fats take
the longest
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Digestive system (gastrointestinal, GI tract)
Pyloric sphincter Duodenum- first section in
the small intestine 10-12 inches long Jejunum-
middle section in the small intestine
8ft Ileum-last section 6-12 ft long, attaches to
the large intestine