2.2.1 Digestion And Enzymes Flashcards
Digestion (2p)
- The breaking down of large insoluble molecules of food into smaller soluble molecules
- They can be absorbed into the bloodstream
Why is digestion necessary
To make sure molecules can be absorbed though the partially permeable membrane and into the blood stream
Substrate
The chemical at the start of the reaction
Active site
The part of the enzyme where the substrate binds
Complementary
When substrate and active site have shapes that fit together
Physical digestion (2p)
- First stage of digestion
- Its quick and breaks down large chunks of food into smaller bits
Example of physical digestion
Chewing
Chemical digestion (2p)
Second stage of digestion
Slower process and chemically breaks down large insoluble molecules into smaller, soluble ones
Examples of chemical digestion (3p)
Enzymes
Digestion by enzymes
Fates are emulsified
Lock and key hypothesis method (3p)
- The substrate and enzyme bind because they are complementary
- So the substrate is broken down
- The enzyme isn’t used up and can be reused
Lock and key hypothesis
explains how enzymes fit their substrate
Why are enzymes specific to one or only a few substrates
Other substrates have the wrong shape so they won’t fit because they aren’t complementary
Amylase
Breaks down carbohydrates into sugar
Protease
Breaks down protein into amino acids
Lipase
breaks down lipids into glycerol and fatty acids
Where is amylase produces (3p)
Saliva
Pancreas
Small intestine
Where is protease produced (3p)
Stomache
Pancreas
Small intestine
Where is lipase found (2p)
Pancreas and small intestine
