Transcript Digestive System - Education Service Center, Region 2
Digestive System
Organs of the Digestive System
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mouth esophagus stomach small intestine large intestine rectum anus pancreas gall bladder liver
Functions of the Digestive System
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Your cells need a lot of energy. They get energy from the food we eat.
But, your digestive system has to break down the food we eat into microscopic nutrients before our cells can use it.
Functions of the Digestive System
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Digests food into molecules the body can use (physical or chemical change).
Absorbs nutrient molecules and carries them around the body (physical change).
Eliminates nutrients.
waste material from unused
mechanical digestion
vocabulary word!
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mechanical digestion - food is physically broken down into smaller pieces by breaking, crushing and mashing.
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increases the surface area of the food begins in the mouth
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teeth chewing/tearing
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movement of smooth muscles
chemical digestion
vocabulary
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word!
chemical digestion - chemicals (enzymes)produced by the body break foods into their smaller nutrients.
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mouth
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stomach
absorption
vocabulary
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word!
absorption - process by which nutrient molecules pass through the wall of your digestive system into your blood.
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The lining of the small intestine is covered in villi that aid in absorption
vocabulary word!
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elimination
elimination
– removal of waste material left over after food is digested to prevent illness.
mouth
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Digestion begins in the mouth
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mechanical – teeth
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chemical - saliva
vocabulary word!
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salivary gland
salivary gland – gland that produces enzymes that help to break down food chemically.
esophagus
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vocabulary word!
esophagus - muscular tube that connects your mouth to your stomach.
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moves food down into your stomach using involuntary muscle contractions (peristalsis).
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Lined with mucus that allows food to slide down.
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vocabulary
stomach
word!
stomach – a muscular bag that crushed food and contains acids and enzymes for breaking down food.
Most mechanical digestion takes place in the stomach because it is made of thick smooth muscle.
Chemical digestions also takes place Mucus keeps the acids from burning a hole in your stomach.
Stomach
vocabulary word!
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small intestine
small intestine – muscular tube where most of the chemical digestion takes place and most nutrients are absorbed.
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Covered in villi which enlarge the surface area
small intestine
The villi increase the surface area that can absorb nutrients.
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vocabulary word!
liver chemicals.
liver
– large organ that produces bile and breaks down medicines and other The gall bladder stores bile
vocabulary
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word!
pancreas
pancreas
- secretes insulin to carry glucose around the body and makes enzymes that help digest food.
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Causes diabetes when it does not make insulin.
large intestine
vocabulary
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word!
large intestine – muscular tube where vitamins B and K are made and water is removed from food waste.
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Food spends 18-24 hours here
rectum and anus
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rectum – end of the large intestine, forms the solid waste
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elimination anus – muscular opening at the end of the rectum
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elimination
The digestive system interacts with:
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muscular system (smooth muscle) to move and digest food.
respiratory system to provide oxygen.
circulatory system to move nutrients.
Which cell parts are like the digestive system?
Which one makes energy?
mitochondria
Which one allows materials to pass in and out?
cell membrane
Which one helps get rid of waste?