1. Bellwork: 9/25 Put your phone up  Week 9/24-9/28
Explain how enzymes work (use the words: active site, chemical reaction, and substrate.
What 2 things alter the enzyme active site?

2. Today:
Enzyme Review
Toothpickase Lab
Properties of Water Notes

3. Materials
Unit II Book
Toothpickase Lab

4. Homework
None 

5. Unit II: Biochemistry

6. Part V: Enzymes

7. Enzymes Types of proteins Speed up chemical reactions
Shapes & function have to match for them to be able to work
Speed up chemical reactions
A million times faster or more

8. Enzymes Enzymes make reactions go faster OR slower
To adjust metabolism
Have names ending in “-ase”
Ex. Lactase(enzyme) breaks down Lactose (Sugar)

9. How Enzymes Work Each enzyme has a unique shape
Works on a specific chemical
Substrate = chemical the enzyme works on
Each enzyme has an active site
VERY SPECIFIC
A slot or pocket that fits substrate perfectly

10. Enzyme

11. Active Site
Shape of Active Site
Complementary to shape of Substrate

12. Environmental Effect
Extreme environments can affect enzyme shape & binding of the Substrate
2 key environmental factors
High Temperature
pH too acidic or too basic
These environments cause the enzyme to denature (break down)

13. Toothpikase Lab

14. Research ?
How does changing shape of the active site and temperature affect the reaction time of enzymes?

15. Lab Toothpicks – substrate Hands – enzyme Fingers – active site
1 student – enzyme
1 student – time the reaction

16. Lab Break 40 toothpicks in half – ONE @ A TIME…Time the reaction!
Break another 40 after you tape 3 of your fingers together on each hand
Break another 40 after you tape 4 of your fingers together on each hand
Untape fingers…THROW TAPE AWAY
Hold both hands in ice water for a minute
Break another 40 toothpicks a time & time
CLEAN UP AND THROW EVERYTHING AWAY 
Answer questions

17. Unit II: Biochemistry

18. Part VII: Properties of Water

19. Water Has a bent shape Oxygen hogs the electrons
Makes O slightly negative
Makes H slightly positive

21. Water Has positive & negative ”poles”
Called “Polar Molecule”
Opposite poles attract to nearby water molecules
Water molecules attract through bonds called Hydrogen Bonds

22. Due to Hydrogen Bonds Water is attracted to itself
Water has special properties

23. Properties Surface Tension Like a “skin” on the surface of water
“Skin” makes water form beads

24. This “skin” holds up water striders

25. 2. Water is attracted to glass & plastic
Both have + and – charges
Water “crawls” up the sides
Forms meniscus

26. Do you think water or ice is more dense?

27. What happens when you freeze a plastic water bottle?

28. 3. Water expands as it freezes

29. Ice forms rigid hydrogen bonds with more spaces between the molecules

30. Due to this, ice floats

31. 4. Water is called “Universal Solvent”
Chemicals with + & - charges dissolve in water

32. Salt water includes Na+ (sodium) and Cl- (chloride)

33. Non-Polar Molecules Don’t have poles (both + & - charges)
Don’t mix with water (don’t dissolve)
Fats, Oils, Waxes