1. Enzymes: Proteins that are used for chemical reactions
Enzymes can either break up or put together substrates
Enzymes are specific – only work on certain substances.
Enzymes are catalysts that react on substrates
Enzymes are NOT CHANGED in the reaction
Textbook pages: Figure 5-5 on pg. 80
You will be responsible for all definitions on pages 1 & 5 of the enzyme packet, and should be able to interpret the graphs on Page 3 of the packet.

2. Definitions:
Proteins: Biochemical compounds (macromolecules) made up of long polymer chains of amino acids linked together
Catalyst: A substance that causes a reaction to occur but does not get changed itself

3. Definitions: Substrate: A substance that the catalyst (enzyme) acts on
Ex) Lactose = milk sugar (substrate)
Lactase = breaks down lactose (enzyme)
Active Site: The specific region of the enzyme that combines with the substrate

5. Lock and Key: The lock is the enzyme and the key is the substrate.
Only the correctly sized key (substrate) fits into the key hole (active site) of the lock (enzyme).

6. Lactose is a 2-unit sugar
Lactose is a 2-unit sugar. Lactase breaks it into 2 individual sugars: glucose and galactose.
Can it break down sucrose as well? Why or why not?

7. Factors that affect the rate of Enzyme Action:
Enzymes work best at certain:
Temperatures pH
Concentrations
(See Graphs- Page 3 of Enzyme Packet)

8. Factors that affect the rate of Enzyme Action:
Temperature: There is an optimum (best) temperature that each enzyme works in . Increase temperature, increase molecule movement, increase rate of the reaction.
Temperature too LOW, decrease the effect of the enzyme
Temperature too HIGH- Protein Denatures (breaks down/changes shape)- the enzyme will not work.

10. Denatured Enzyme

11. Factors that affect the rate of Enzyme Action:
pH: Enzymes work best at different pH levels depending on where they are. Page 4- Enzyme Packet: Relative Rate of Enzyme Action.
pH Scale?
Acidic = 0 – Basic = 7.1 – 14
#3- Enzyme A- pH of the stomach?
#4- Enzyme B- pH of the intestine?

12. Factors that affect the rate of Enzyme Action:
Concentration:
Increasing the amount of enzyme will increase the rate of reaction, but it will eventually level off- why?
For the same reason, increasing the substrate concentration will increase the rate of reaction, but it will eventually level off.

13. SEE ALL GRAPHS ON PAGE 3 of the Enzyme Packet

14. Activation Energy The energy needed to start a chemical reaction.
Similar to rolling a boulder downhill, it is the chemical ‘push’ that gets a chemical reaction going.
Enzymes lower the activation energy needed for chemical reactions. Less energy needed to start the reaction, can occur at lower temperatures.

15. Activation Energy Endothermic: Building

16. Activation Energy Exothermic: Breakdown

17. Enzyme Animation http://www.biotopics.co.uk/other/hienz.html

18. How Enzymes Work
The active site (location on the enzyme where the substrate fits and the reaction takes place) on the enzyme attaches to a substrate molecule
While attached to the substrate, the enzyme either breaks or makes a bond, resulting a change to the substrate
Ex) Carbohydrate broken into sugars
Amino acids bonded to make protein
The enzyme is not changed during the reaction and is free to break-down more substrates

19. CAPT LAB: ENZYMES
Comparing the effectiveness of cellulase and pectinase in making juice.
You will investigate which enzyme or combination of enzymes will remove more juice during the process of making apple juice from applesauce .
Once you complete the lab, you will evaluate which enzyme will be the most cost effective plan to use in juice production.

20. CELLULOSE Large carbohydrate Composes the cell walls of plants
Tough and fibrous – provides structure to plants

21. CELLULASE The enzyme that breaks down cellulose
The optimum pH generally lies between 4 and 5

22. Pectin Large carbohydrate found in plant cell walls
Sticky substance used to bind plant cell walls to each other and hold cellulose in place

23. Pectinase Enzyme that breaks down the pectin in plant cells
Used to produce fruit juice and wine
Optimum pH is 4-5

24. CAPT Lab: Cellulase v. Pectinase
Enzymes?
Pectinase and Cellulase
Substrates?
Apple Sauce

25. CAPT LAB: Purpose
To determine which enzyme, or combination of enzymes, will produce the most juice for the least cost