Digestive System Breaking down food to be used by the body.
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Transcript of Digestive System Breaking down food to be used by the body.
Digestive SystemBreaking down food to be used by
the body
Mouth
1.Mechanical Digestion – break up of food=chewing
2.Beginning of Chemical Digestion
Saliva from Salivary Gland- breaks down starches into simpler sugars
Function
Esophagus
• Food tube- contraction of muscle rings push food to the stomach (Peristalsis)
• Think: Where does food go if it “goes down the wrong pipe?”
Function
Stomach
• Mechanical-Food mixes-becomes Chyme
• Chemical Digestion-
-Mostly digests some proteins
Function
Small Intestine
• MOST nutrient absorption takes place here!
• Enzymes in the small intestine come from the pancreas and liver.
• Basic environment (not acid) helps neutralize acid from stomach.
• As chyme enters: – No fat digestion has taken
place yet!
Function
Liver
• Secretes Bile into beginning of small intestine– Helps to break down
fats by preventing their sticking together so enzymes can attack
– Not an Enzyme!– Works like dish-
washing soap
• The Gall Bladder stores the bile
Function
Chemical Digestion: Fats
Figure 23.35
Like soaping your body!Or the dishes!
Pancreas
• Secretes Sodium Bicarbonate– base that neutralizes
acid in small intestine
• Many chemicals used in digestion come from the pancreas
• All remaining digestion happens in small intestines
Function
Hidden behind stomach
Large Intestine (Colon)
• Removes WATER from undigested material
• What happens when not enough water is removed?
• Some GOOD bacteria live here– Breakdown indigestible
carbohydrates (lactose)– Synthesize B complex
vitamins and vitamin K
Function