Transcript Physical vs. Chemical Changes in Digestion

DIGESTIVE
SYSTEM
Mouth
Liver
Salivary Glands
Esophogus
Stomach
Pancreas
Large intestine
Small intestine
Rectum
Anus
The Digestive System
Purpose:
• Break down food into small pieces that
cells can use.
How is food digested?
• Mechanical break down of food into smaller
pieces = physical change
• Mixing of food
• Movement through the digestive tract
• Chemical break down of big molecules of
food into smaller molecules = chemical
change
Mouth
• Physical (Mechanical) digestion –
teeth
• Chewing – breaks food into
small pieces
•Chemical digestion – saliva
• Enzymes in the saliva begin
digestion of carbohydrates.
• Muscular tube
Esophagus
• Physically moves food to
stomach using waves of
muscle contractions called
peristalsis.
Stomach
• Produces strong
digestive juices.
•Chemical Digestion breaks
down and dissolves food
nutrients.
•Digests proteins and fats in
the stomach
Small Intestine
• Enzymes continue the
chemical digestion of
food.
•Nutrients are broken down
small enough to go through
the VILLI of small intestine,
and into blood
•Digests proteins, fats, and
carbohydrates. Digestion
Completed Here
Pancreas
• Accessory organ
•Food does not enter the
pancreas
•Produces chemicals to
help break down
macromolecules (big
molecules) = chemical
difestion
Liver
• Produces bile to help
digest fat = mechanical
digestion = physical change
• Bile is Stored in the
Gallbladder
Large Intestine (Colon)
• Absorbs dissolved nutrients & water
• NO DIGESTION
•Forms wastes into solid feces
•Physical Change
Rectum
• Compacts and stores solid waste
Anus
• Opening through which “feces” = solid waste
leaves the body
• Voluntary Action
Mouth
Liver
Salivary Glands
Esophogus
Stomach
Pancreas
Large intestine
Small intestine
Rectum
Anus