1. CHEMICAL REACTIONS
Process which changes one set of chemicals into another set of chemicals.
Ex. Combining Iron (Fe) and Oxygen (O) to form Rust.
Reactants - elements or compounds that enter into a chemical reaction
Products - elements or compounds made by a chemical reaction.
Bonds are broken in reactants and formed in products.

2. CHEMICAL REACTIONS ALWAYS INVOLVE CHANGES IN ENERGY
REACTIONS THAT RELEASE ENERGY SOMETIMES HAPPEN SPONTANEOUSLY
REACTIONS THAT ABSORB ENERGY MUST HAVE A SOURCE OF ENERGY
THE ENERGY NEEDED TO START A REACTION IS CALLED ACTIVATION ENERGY.

3. CATALYSTS SUBSTANCES THAT SPEED UP RATE OF REACTION.
WORK BY LOWERING THE ACTIVATION ENERGY.
ENZYMES ARE PROTEINS THAT SPEED UP CHEMICAL REACTIONS IN CELLS. CAUSES THE REACTION TO TAKE PLACE BY LOWERING THE ACTIVATION ENERGY NEEDED.
EX. CO2 + H2O  H2CO3
Carbonic anhydrase

4. SPEED OF REACTIONS
LEFT ALONE MANY BIOLOGICAL REACTIONS WOULD HAPPEN TOO SLOWLY.
Example of an enzyme
CARBONIC ANHYDRASE CAUSES THE CHANGE INTO CARBONIC ACID TO HAPPEN QUICKLY.
ENZYMES ARE SPECIFIC AND USUALLY ONLY CATALYZE ONE REACTION.

5. ENZYME ACTION
REACTANTS IN CHEMICAL REACTIONS MUST HIT WITH ENOUGH FORCE TO BREAK OLD BONDS AND FORM NEW ONES
ENZYMES PROVIDE THE PLACE WHERE REACTANTS ARE BROUGHT TOGETHER REDUCING THE ENERGY NEEDED FOR THE REACTION TO OCCUR.

6. ENZYME SHAPE SUBSTRATES - THE REACTANTS OF ENZYME CATALYZED REACTIONS
EACH PROTEIN HAS A SPECIFIC SHAPE.
ACTIVE SITE ON THE PROTEIN HAS A COMPLIMENTARY SHAPE TO THE SUBSTRATE.
ENZYME AND PROTEIN FIT TOGETHER LIKE PUZZLE PIECES.
SEE PG. 52
ENZYMES ARE REUSABLE.

7. ENZYME ACTIVITY AFFECTED BY Ph
Many biological enzymes function best at a pH of 7
Most biological enzymes function best at normal human body temp.
Few enzymes function well at high temperature

8. Activation Energy
What significance do these energy changes have to do with living things?
In order to stay alive, organisms need to carry out reactions that require energy.

9. Regulation of Enzyme Activity
Because they are catalysts for reactions, enzymes can be affected by any variable that influences a chemical reaction.
Many enzymes are affected by temp, pH, etc.

10. http://www. youtube. com/watch
Difference between no enzyme and enzyme in solution Awesome Animation
How enzymes work in the body!