1. Starch—Break It Down!
p. 369

2. What is an enzyme?
A protein found in organisms with a specific function.
Examples: Protease breaks down proteins
Lipase breaks down lipids
Amylase breaks down carbs
Where do you think these enzymes are found?
What is similar between the 3 enzymes?

3. Function of Enzymes
Reduce the amount of activation energy needed to start a chemical reaction. As a result the enzyme acts as a catalyst by speeding up the reaction.
Ex. Digestion would take a lot longer w/o enzymes!
Control very specific reactions (see lock and key model)
Breakdown reactions, ex. Digestion
Synthesis reactions, ex. Protein Synthesis (making of proteins from ?????)

4. Progress of the reaction
Course of
reaction
without
enzyme EA
without
enzyme
EA with
enzyme
is lower
Reactants
Course of
reaction
with enzyme
Free energy
Change in free energy
(∆G ) is unaffected
by enzyme
Products
Progress of the reaction

5. Lock & Key Model Enzymes are substrate specific! Substrate
Observe the picture above. Provide evidence
that supports the claim that enzymes are
substrate specific.
Enzyme

6. Enzyme Function
(Hydrogen Peroxide) +
H2O O2
(Products)

7. Purpose of this lab! (See NTK Box, p. 370-71)
Your team will investigate the role of amylase in breaking down starch into smaller molecules called maltose and glucose.
How do different variables affect enzyme reactions?

8. Variables (circle one)
Amylase Concentration
Starch Concentration
Temperature
pH (acidic or basic environment)

9. Guidelines You will be observing: The amount of glucose produced.
The presence of starch.
You will collect data:
0 minutes
4 minutes
You must use both amylase and starch, but change only 1 variable!
Note: You are doing this for all 3 concentrations, temperatures, or pH’s