1. Tuesday, 9/5
1.) While eating a peanut butter sandwich (on whole wheat), Ms. Muck decided to find out which macromolecules were present in the sandwich. Which biochemical tests do you think would be positive for the nutrients in this sandwich?
2.) Tell me the five functional groups. In which macromolecule(s) would each be found?

2. Homework/Upcoming Assignments
1.) Macromolecule QUIZ (not a test) on Wednesday, 9/6 and Thursday, 9/7
2.) After you finish quiz, you will work on your Enzyme Foldable (due on Test Day). I will go over instructions and show you an example.
3.) UNIT 1 TEST (Chapters 1, 2, & 3): Multiple-choice AND FRQ on Tuesday, 9/12 (Pds. 2, 4, 6) and Wednesday, 9/13 (Pds. 1, 3, 7)
Study Guide given on Friday; Review on Monday

3. Word of the Day
Misanthrope (noun)
A person who hates or distrusts humankind
“The man was a misanthrope who surrounded his entire yard with barbed wire to keep his neighbors at bay.”

4. Enzymes

5. What Are Enzymes? Most enzymes are proteins
Act as catalysts to accelerate a reaction
Not permanently changed in the process
Can be reused

6. Enzymes Are specific for what they will catalyze Are reusable
End in –ase
-Sucrase
-Lactase
-Maltase

7. How do enzymes work?
Enzymes work by weakening bonds of the reactant, which lowers activation energy (energy needed to start the reaction)

8. Enzymes Without Enzyme With Enzyme Free Energy
Progress of the reaction
Reactants
Products
Free energy of activation

9. Substrates The substance (reactant) an enzyme acts on is the substrate
Joins
Substrate

10. Active Site
A restricted region of an enzyme molecule which binds to the substrate.
Active Site
Enzyme
Enzyme + Substrate = ENZYME-SUBSTRATE COMPLEX
Substrate

11. How does a substrate fit with its enzyme?
TWO MODELS:
1.) Lock-and-Key Model
2.) Induced Fit Model

12. Lock-and-Key
Active Sites are SPECIFIC and COMPLEMENTARY for their substrates.
This is like a LOCK & KEY
Idea of “1 substrate for 1 enzyme”

13. Induced Fit A change in the shape of an enzyme’s active site
Induced by the substrate
Idea that 1 enzyme can have more than 1 substrate. Is still specific for its substrates, but may be more than 1

14. Induced Fit
A change in the configuration (shape) of an enzyme’s active site
Induced by the substrate.
Enzyme
Active Site
substrate
induced fit

15. What Affects Enzyme Activity?
Three factors:
1. Environmental Conditions
2. Cofactors and Coenzymes
3. Enzyme Inhibitors

16. Environmental Conditions
1. Extreme temperatures are the most dangerous
- High fevers
2. pH (most like pH near neutral)
3. Ionic concentration (salt ions)
ALL OF THESE FACTORS DISRUPT THE SHAPE OF THE ENZYME, SO IT WILL UNFOLD (DENATURE)

17. Cofactors and Coenzymes
1. Metal ions (zinc, iron) = Cofactors (nonorganic)
2. Vitamins (biotin, B12) = Coenzymes (organic)
Sometimes need for proper enzymatic activity…help to further speed up the reaction
Example: Iron (Cofactor) must be present in the structure of hemoglobin in order for it to pick up oxygen.

18. Enzyme Inhibitors: 1st Type
1. Competitive inhibitors: chemicals that resemble an enzyme’s normal substrate and compete with it for the active site.
Enzyme
Substrate
Competitive inhibitor

19. Enzyme Inhibitors: 2nd Type
2. Noncompetitive inhibitors:
Inhibitors that do not enter the active site, but bind to another part of the enzyme causing the enzyme to change its shape, which in turn alters the active site.
Enzyme
Noncompetitive
Inhibitor
Substrate
active site
altered

20. POINTS TO REMEMBER Most are PROTEINS Act as CATALYSTS
 ACTIVATION ENERGY
SPEED  Reactions
Provide an ACTIVE SITE to bind to its substrate and form an enzyme-substrate complex
Are SPECIFIC for its substrate(s)
Are REUSABLE (after converting a reactant to product, can do this multiple times!)