1. Energy and Enzymes
Section 2.4

2. Chemical Reactions Reactions create energy transfer
Energy – the ability to do work or cause changes
Chemical reaction: Reactants  Products
Ex. H2O + CO2  H2CO3
Reactions create energy transfer
Exergonic Reactions - __________ free energy

3. Chemical Reactions Reactions create energy transfer
Energy – the ability to do work or cause changes
Chemical reaction: Reactants  Products
Ex. H2O + CO2  H2CO3
Reactions create energy transfer
Exergonic Reactions - ___release_ free energy
Endergonic Reactions - _________ free energy

4. Chemical Reactions Reactions create energy transfer
Energy – the ability to do work or cause changes
Chemical reaction: Reactants  Products
Ex. H2O + CO2  H2CO3
Reactions create energy transfer
Exergonic Reactions - ___release_ free energy
Endergonic Reactions - __absorb_ free energy

5. Activation energy – energy needed to start a reaction.
Catalysts – chemical substances that reduce the amount of activation energy needed for a reaction. Ex. _______

7. Enzymes
Enzymes speed up reactions by lowering the activation energy needed for a reaction
Enzyme binds to substrate
Enzymes are substrate-specific (1E = 1S)
(like a lock and key)

8. Factors that affect Enzyme Activity
Temperature
Concentration pH
Regulatory molecules