Enzymes help to start and run chemical reactions

 What is a catalyst? A catalyst is a substance that decreases the activation energy needed to start a chemical reaction and increase the rate of chemical reactions.

 Catalysts Activation energy comes from an increase in temperature Without a catalyst a chemical reaction can take a while to start. Catalysts are not considered reactants or products because they are not used up during a reaction.

 Define enzymes Proteins that change the rate of a chemical reaction. In other words…helps speed up the chemical reactions that would occur very slow normally.

 What major process in the body are enzymes important for? Food Digestion

 Enzymes Act as catalyst (boosters) How do enzymes speed up chemical reactions? → By lowering the activation level Activation level is the amount of energy needed to kick start a chemical reaction.

Factors that Affect Enzyme Reaction Rates. Normal Enzyme Reaction Rate Bell Shape Curve Enzyme Reaction Rate Amt. of Enzyme Colder Temps = Slows Down Reaction Rate Warmer Temps = Speed Up Reaction Rate Reaction Rate Reaction Rate Amt. of Enzyme Amt. of Enzyme

 Factors that Affect Enzyme Reaction Rates. pH If an enzyme’s environment is TOO ACIDIC or TOO BASIC… If an enzyme’s environment is EXTREMELY COLD or EXTREMELY HOT… X Denature = When enzymes break down and die.

How Do Enzymes Change the Rate of a Reaction? Step #1 Enzymes bind to specific substrates at the active site. Substrate is the compound being broken down into smaller molecules.

Enzyme Reaction Rate Step #2 Enzymes change shape in order to bind with the substrate.

Enzyme Reaction Rate Step #3 Substrate bond is broken. Smaller molecules are released.

Enzyme Reaction Rate Step #4 Enzyme returns back to original shape. Cycle repeats.

Enzyme Reaction Rate Lock and Key Method

https://www.youtube.com/watch?v=XTUm-75-PL4 https://www.youtube.com/watch?v=NdMVRL4oaUo