You’re eating a carrot… 1. you begin to chew (manual breakdown) 2. you are salivating as you chew  Amylase in salvia  Amylase is a digestive enzyme classified as a saccharidase (an enzyme that breaks down polysaccharides). 3. Amylase is an ENZYME What is an enzyme?  GOOD QUESTION!

Enzymes

Function of Enzymes Enzymes speed up the rate of reactions  Enzymes can be called catalysts Catalysts speed up reactions They do NOT  Change the reaction

Enzymes Most enzymes are proteins. Not all proteins are enzymes.

Enzymes and Substrates Enzymes affect substrates  Substrate- substance on which an enzyme acts specific enzymes can only fit with specific substrates-  called SPECIFICITY  lock and key model

All pictures demonstrate the same thing. A perfect fit between enzyme shape and substrate shape.

Active Site Active sites are where the enzyme and substrate will meet when they create the enzyme-substrate complex.

Enzymes Shape determines function  enzymes are very specific in their function Under normal conditions, enzymes do not change shape even after they perform their function.  This means that enzymes can be used over and over again.

Enzymes speed up reactions that would happen normally…

Enzymes Enzymes are catalysts.  enzymes speed up the rate of reactions in living things Chemical Reaction:  Reactants and products  Ex. Reactants Products

Reaction with an enzyme Enzymes bind temporarily to the reactants of the reaction. In doing so, they lower the amount of activation energy needed to start the reaction. Therefore, reaction time is increased.

Enzymes Activation energy refers to the amount of energy a system needs to initiate a process.

Enzymes

Two factors can affect the shape of an enzyme:  temperature  pH  Denature

Enzymes: OPTIMAL RANGE Enzymes works best when in their proper environment activity decreases at values above and below its optimal range. Ex.

Exit Card 1. Look at the picture. Name parts: A, B, C, D and E