1. Enzymes

2. Activation Energy energy needed to start a chemical reaction
ex: spark plug in an engine

3. Hydrolysis of Sucrose by Sucrase
Enzymes
enzymes are biological catalysts
catalyst
substances that reduce the activation energy of a chemical reaction
reducing activation energy allows the reaction to occur more frequently and faster
Hydrolysis of Sucrose by Sucrase
McGraw - Hill

4. Enzymes & Activation Energy
Reaction pathway
without enzyme
Activation energy
Activation
energy
with enzyme
Reactants
Products

5. What type of macromolecule are most enzymes?
enzymes are proteins
these proteins (enzymes) increase the speed of chemical reactions
some enzymes break molecules apart

7. What type of macromolecule are most enzymes?
enzymes are proteins
these proteins enzymes increase the speed of chemical reactions
some enzymes break molecules apart
other enzymes put molecules together

9. What type of macromolecule are enzymes?
enzymes are proteins
these proteins (enzymes) increase the speed of chemical reactions
some enzymes break molecules apart
other enzymes put molecules together
do not get used up in a chemical reaction
help maintain homeostasis

10. Substrate substance on which an enzyme acts during a chemical reaction
substrate = reactants

12. Active Site How Enzymes Work McGraw - Hill
the location on an enzyme that attaches to a substrate
How Enzymes Work
McGraw - Hill

14. Enzyme Specificity
enzymes are specific because only its substrate fits into its active site
enzymes are similar to a lock and key

15. Enzyme Efficiency work well only within a certain set of conditions
changes in conditions like pH and temperature can change the shape of the protein (called denatured)
when the substrate no longer fits the active site, the enzyme will not work
the “lock and key” no longer fit in one another

16. lactose  glucose + galactose
Example
lactase is an enzyme that breaks down milk sugar (lactose)
lactase
lactose  glucose + galactose

17. lactose  glucose + galactose
Why is lactase written above the arrow and not included in the chemical equation?
because enzymes (like lactase) are not used up in chemical reactions
they can be re-used over and over again for the same type of reaction
lactase
lactose  glucose + galactose