1. Enzymes

2. Enzymes
Protein that acts as catalyst in an organism to speed up reactions

3. Enzymes
Enzymes speed up reactions by lowering activation energy required

4. Enzymes
Enzymes speed up reactions by lowering activation energy required

5. Enzymes
Lower activation energy = less time needed for reaction

6. Enzyme Shape
Enzymes have specific shapes that allow them to do their function
(like all proteins)

7. Substrate
Particle upon which enzyme is acting

8. Active Site Where substrate and enzyme bond
Active site has specific shape that can only receive 1 specific substrate

9. Active Site

10. Lock and Key Fit Model
Substrate and enzyme bond with exact matching shapes; lock and key specificity

11. Induced Fit Model
Substrate has similar but not exact shape as active site; enzyme conforms to substrate (like a glove conforming to a hand)

12. Cofactors and Coenzymes
Cofactor – non-protein that helps fill inactive site
Often metal ions (copper, heme)
Coenzyme – protein that helps fill active site
Often derived from vitamins

13. Cofactors and Coenzymes

14. Enzymes are Reusable! After a reaction, an enzyme can be reused
Just like after using scissors to catalyze the cutting of paper, the scissors can be reused