Digestion, moving on

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Digestion, moving on

• Karen Kraus
• BIOL 204
• November 6, 2007

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Feeling it in the gut
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Can you stomach this?

• Mucosa
• Gastric pits
• Mucous neck cells
• Parietal cells
• Chief cells
• Enteroendocrine cells
• Submucosa
• Muscularis

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What goes down must come

• Water, mucus, HCl, intrinsic factor, enzymes
• Pepsin, rennin, lipase
• Hormonal control
• X (PNS)
• celiac plexus (SNS)

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Youve got some guts
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The little things.
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specialization

• Mucosa
• Crypts of Lieberkuhns
• Paneth cells
• Submucosa
• Brunners glands
• Peyers patches

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Da juice

• Mostly water
• Barely basic
• Enzymes
• Enterokinase
• Various disaccharidases
• Peptidases
• Lipases
• Controlled by PNS (X), secretin,
  distension/irritation and acidity

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With onions

• Four lobes divided into lobules
• Hepatocytes form bile
• Sinusoids filter blood
• Various functions
• Gall bladder stores and concentrates bile until
  it is released

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Bile

• Water
• HCO3-
• Bile salts
• Cholesterol
• Bile pigments
• Lipids/phospholipids
• Lecithin
• Other electrolytes
• Emulsifies fats for lipase

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Panacea

• Endocrine and exocrine functions
• Acinar cells are exocrine
• HCO3-
• Proteinases
• Amylase
• Exonucleases
• Lipase

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Its big!
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colonoscopy

• Symbiotic bacterial action
• Water reabsorption
• Electrolyte reabsorption
• Feces formation

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The end

• Haustral contractions and mass movements
• Defecation reflex
• Distention
• Contraction of the rectal muscles
• Anal sphincters
• Levator ani