What Happens to Food Once it Enters Your Mouth?

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What Happens to Food Once it Enters Your Mouth?
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Digestion the process that breaks down food
into small molecules that can be absorbed and
moved into blood.

• Mechanical Digestion takes place when food is
  chewed, mixed, and churned.
• Happens in the mouth, esophagus, and stomach.

• Chemical Digestion takes place when chemical
  reactions break down large food molecules into
  smaller ones.
• Happens in the mouth, stomach, small intestine.

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Enzymes

• Proteins that speed
• up reactions without
• being used up.
• Enzymes are very
• important to the
• digestive process.

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Organs of the Digestive System

• Digestive Tract mouth, esophagus, stomach,
  small intestine, large intestine, rectum, anus.
  All food passes through these organs.
• Accessory Organs tongue, teeth, salivary
  glands, liver, gall bladder, and pancreas. Liver,
  gall bladder, and pancreas make and store enzymes.

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The Mouth both mechanical and chemical
digestion happen here.
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The Esophagus

• About 25 cm long.
• Takes about 4-10 seconds for food to reach the
  stomach.
• Peristalsis moves food down the esophagus.
• No digestion occurs here.

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The Stomach

• Mechanical and chemical digestion happen here.
• Hydrochloric acid and enzymes break down food and
  kill bacteria.
• Food leaves in 2-4 hours as a thin, watery liquid
  called chyme.

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The Small Intestine

• About 4-7 m in length.
• Many enzymes are mixed with food here.
• Covered with villi to increase surface area.
• Food molecules are absorbed here and released
  into the bloodstream.

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Small Intestine and Villi
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Large Intestine

• Main job is to absorb water back into the body
  from chyme.
• Peristalsis slows down here meaning food stays
  for up to 3 days.
• Semi-solid wastes are released by the rectum and
  anus.

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Bacteria

• Are very important to the digestive process.
• Feed on undigested material in large intestine.
• Produce vitamins.
• Also produce gas.

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Digestive System

• Chemical and physical digestion.
• Ingestion happens in the mouth digestion occurs
  in the mouth, stomach, and small intestine
  absorption occurs in the small and large
  intestine.
• Accessory organs move and cut up food and supply
  enzymes and other chemicals.
• Large intestine reabsorbs water.

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One last look