Cells use catalysts to speed up chemical reactions by reducing the activation energy required. Catalysts work by lowering the energy barrier of a reaction without being used up in the process, allowing reactions to occur faster and with less energy. The most common type of catalyst in living things are enzymes, which are proteins that catalyze biochemical reactions and help processes like digestion occur quicker without changing their own structure.

1. Catalysts

2. Vocabulary
 How do cells regulate chemical reaction rates?
 Cells use catalysts
 Activation Energy – the amount of energy needed to
start the reaction.
 Catalysts – is a substance that speeds up a chemical
reaction by reducing the amount of activation energy
required.

3. Catalysts
By using catalysts, chemical reactions will occur
quicker and work faster to make a product.
 In general, these are the attributes of catalysts:
 They speed up the rate of a reaction
 They cannot cause an unfavorable reaction to
occur.
 They won’t change the equilibrium
 Catalysts are not consumed
 Higher temperatures speed up a catalysts
 Each catalysts has a pH that it works best at.

4. Enzymes
 Most common type of catalysts are enzymes.
 Enzyme – Are a protein that catalyzes a biochemical
reaction without changing its own structure or function.
 Ex. Enzymes in your saliva help you digest food quicker