1. Enzymes
Biology 12

2. Enzymes Take notes as the video goes Generally what is an enzyme?
How does an enzyme react to only one substrate?
How do you stop the enzyme when you do not want it working?

3. Metabolism
The sum of all the chemical reactions in a cell Anabolic- build up Catabolic - break apart

4. Enzyme function
Active site - small part of enzyme involved in reaction Lock & Key - substrate fits into active site Induced fit - Active sit undergoes slight shape change in order to fit substrate

5. Enzyme Reactions
Synthesis Reaction (anabolism)

6. Enzyme Reactions
Degradation Reaction (catabolism)

7. Denatured Enzyme

8. Enzyme Examples- Specificity
Substrate Enzyme
Lipid
Lipase
Maltose
Maltase
Lactose
Lactase
Polypeptides
pepsin

9. How do enzymes speed up rxn?
Activation energy - amount of energy needed to get rxn to proceed Enzymes lower the activation energy

10. Factors that affect enzyme activity
Substrate & enzyme concentration
-more reactants = more rxn can occur
Temperature C
-lower temp, enzyme less flexible… affects induced fit
3. pH- 6-8 (most)
-denature protein in pH is too high/ low

11. Factors that affect enzyme activity
4. Inhibitors
Competitive- competes with same active site (substrate can’t bind so enzyme can’t work)
Non-competitive- binds to allosteric site (not active site) and causes shape change of active site (substrate wont fit in active site)

12. Factors that affect enzyme activity
Cofactors
-fit into allosteric site & assist enzyme activity (change shape of active site to FIT substrate)
1) Organic - Vitamins, haeme, flavin
2) Non-organic - metal ions (Mg 2+,Cu 2+,Mn2+)

13. Enzymes Song