1. Enzymes

2. KEY CONCEPTS:
Enzymes help chemical reactions to occur

3. Catalysts are substances that speed up chemical reactions.
Decrease Activation Energy
Increase Reaction Rate

4. Enzymes are catalysts in living things
Enzymes are needed for almost all processes.
Most enzymes are proteins
Enzymes are not used up in reactions!

6. Disruptions in homeostasis can prevent enzymes from functioning.
Enzymes function best in a small range of conditions
Changes in temperature and pH can break apart enzymes and cause them to stop working
An enzyme’s function depends on its structure

7. An enzyme’s structure allows only certain reactants to bind to the enzyme.
The reactants in an enzyme-catalyzed reaction are called Substrates
The substrates interact with the enzyme at the Active Site

8. substrates (reactants)
enzyme
Substrates bind to an enzyme at certain places called active sites.

10. The lock-and-key model helps illustrate how enzymes function.
substrates brought together & combined into products
Each enzyme only catalyzes one type of reaction
Substrates bind to an enzyme at certain places called active sites.
The enzyme brings substrates together and weakens their bonds.
The catalyzed reaction forms a product that is released from the enzyme.

11. CHECK for Understanding!
Energy of Reactants: A
Normal Activation Energy: B
Activation Energy w/ Enzyme: C
Energy of Products: D
Endothermic or Exothermic?
Exothermic

12. CHECK for Understanding!
Reactant? A
Substrate?
Enzyme? B
Products? E