1. Enzymes Biological catalysts
18.11-Explain the role of enzymes as catalysts that lower the activation energy of biochemical reactions. Identify factors such as pH and temperature, and their effect on enzyme activity.

2. Enzymes
Objective: Investigate and report factors (e.g. surface area, pH, catalysts, and temperature) that affect the rate of reaction among atoms and molecules
EQ: How do different environmental factors affect enzyme activity?

3. Chemical Reactions
A chemical reaction changes the original substances (chemicals) into new, different substances
Bonds break and form
Reactants: the compounds that you begin with; substances that are changed by the reaction
On the LEFT side of a reaction equation
Products: the compounds that you end with (what the reaction produces) *think math*
On the RIGHT side of a reaction equation

4. Chemical Reactions
Photosynthesis is a chemical reaction 6 CO2 + 6 H2O  C6H12O6 + 6 O2 Which compounds are products and which are reactants?
direction

5. Photosynthesis is a chemical reaction 6 CO2+ 6 H2O  C6H12O6 + 6 O2
Chemical Reactions
Photosynthesis is a chemical reaction 6 CO2+ 6 H2O  C6H12O6 + 6 O2
direction
Products (what we end with)
Reactants (what we started with)

6. Activation Energy
Activation Energy: the energy required for a reaction to begin
Like the energy needed to push a ball up a hill; once at the top, the ball will roll down the other side of the hill on its own

7. Types of Reactions
Exothermic: overall, energy is released by the reaction
Extra energy
given off as heat,
light, etc.

8. Types of Reactions
Endothermic: overall, energy is absorbed by the reaction
The reaction will feel cold

9. Check for Understanding
Identify the reaction as endothermic or exothermic.
Exothermic!

10. Check for Understanding
Identify the reaction as endothermic or exothermic.
Endothermic!

11. Check for Understanding
Identify the reaction as endothermic or exothermic.
Exothermic!

12. Check for Understanding
Just for fun…

13. Catalysts Catalyst is reuseable! (not changes by the reaction)
A catalyst is a substance that speeds up the rate of a chemical reaction by lowering the activation energy
Catalyst is reuseable! (not changes by the reaction)

14. Enzymes act as biological catalysts
Enzymes are catalysts in living things.
Catalase is the enzyme that catalyses the break down of hydrogen peroxide.
Catalase

15. hydrogen peroxide water + oxygen 2H2O2 2H2O + O2
Hydrogen peroxide breaks down to water and oxygen
hydrogen peroxide
manganese oxide
water + oxygen
2H2O2
2H2O + O2
The escaping oxygen causes the foaming

17. Enzyme Lab Honors What is the purpose of the lab?
What reaction are we observing?
What enzyme are we using?
What are you testing in each part of the lab?

18. Enzyme Lab
Working in groups, you will complete the lab to see the affects of temperature, pH, and concentration on enzyme activity.
C- level 2 voices
H- ask your lab group, then raise a silent hand
A- complete enzyme investigation
M- remain at your assigned lab table until complete, then clean up once you’re done & take your assigned table seat
P- work with your group to collect data but each member of the team must turn in their own copy
SUCCESS!

19. Enzyme Lab Review
What is the affect of concentration on enzyme reaction rate? How do you know based on your results?
What is the effect of Temperature on enzyme reaction rate? How do you know based on your results?
What is the affect of pH on enzyme activity? How do you know based on your results?

20. What factors affect enzyme activity?
Exit ticket
Clear your desk
What factors affect enzyme activity?