1. #1 Explain the role of the chloroplast.
Which organelle surrounds the cell and is selectively permeable?
Which organelle is the powerhouse of the cell?
Apoptosis is programmed .
Which type of transport does not require energy?
Answers:

3. Chemical Reactions
Chemical reactions = the breaking and creating of bonds between different substances (this requires energy)
Activation energy = The amount of energy needed to make a chemical reaction start

4. Chemical Reactions
Reactants (substrate): substances that are changed during a reaction
Products: substances that are made by a chemical reaction
reactants
products

5. Types of Reactions Overall, reactions absorb or release energy.
Endothermic: absorbs energy
Ex. Photosynthesis
Exothermic: releases energy
Ex. Cellular Respiration
EXOTHERMIC
ENDOTHERMIC
Less energy in products than reactants
More energy in products than reactants

6. Key Biochemical Reactions
6CO2 + 6H2O + (Light energy)  C6H12O6 + 6O2 Photosynthesis Energy is stored as sugar, therefore it is an ENDOTHERMIC reaction C6H12O6 + 6O2  (chemical energy) + 6CO2 + 6H2O Cellular Respiration Energy is released as ATP when sugar is broken down, therefore it is an EXOTHERMIC reaction

7. Enzymes
Enzymes are a type of PROTEIN that speed up biochemical reactions by lowering the activation energy.
Because they speed up reactions, they are called catalysts.
Enzymes are specialized molecules that bind to reactants (aka, substrate) and help to break or form bonds. Then they release a newly created product.
Enzymes are not changed in a reaction and can be used over and over again!

8. Enzymes Enzymes are very specific
They have an active site that fits only one substrate (reactant)
This is known as the lock and key model
substrate
(reactant)
active site
enzyme

9. Enzymes Enzymes can break bonds in a substrate to form two products
(Bonds breaking)
enzyme

10. Enzymes Enzymes can make bonds between substrates to form one product
(Bonds forming)
enzyme

11. Denaturation
Enzyme’s active site gets deformed and loses its specific shape  causes a loss of biological activity
Caused by: extreme changes in pH, temperature, ion strength, and solubility
Enzymes can be “renatured” to their original shape but not always
Normal enzyme
Denatured enzyme

12. Ways to change the rate of a chemical reaction
Temperature = increasing temperature increases the rate of the reaction
Molecules are moving FASTER and colliding more with each other
2. pH = how acidic a solution is
Most enzymes only work at very specific pH so if the pH changes it can affect speed of reaction

13. Ways to change the rate of a chemical reaction
3. Substrate Concentration = the higher the amount of substrate, the faster the reaction
Due to more particle collisions
4. Catalysts = (like enzymes) speed up reactions
Lower activation energy needed for the reaction to start
5. Competitive Inhibitor = slows down reaction
Competes with substrate for the active site on the enzyme

14. Vocabulary Cards Chemical Reactions Activation Energy Reactants
Products
Endothermic
Exothermic
Enzyme
Active Site
Denaturation
Vocabulary Cards

15. Exit Ticket
Describe an enzyme.

16. #2
When fireflies give off light a reaction takes place. Is this an example of endothermic or exothermic reaction?
What happens to an enzyme during denaturation and can it be reversed?
What does an enzyme do to a reaction?
& 5. Name two things that can affect the rate of a reaction.
Answers:
Exothermic (1)
It loses its biological activity due to change in active site and it can be reversed (but it rare) (1)
Speeds it up by lowering the activation energy (1)
Answers may vary. catalyst, catalyst concentration, substrate concentration, temperature, pH, competitive inhibitor, coenzyme, etc. (2)

17. #3 Reactants are (used/made) in a reaction.
Products are (used/made) in a reaction.
3.-5. Draw a picture of the lock and key model. Label the (3.) enzyme, (4.) active site, and (5.)substrate.
Answers:
Used/broken (1)
Made/produced (1)
Active site labeled where substrate is bond to enzyme. (3)

18. #4 In a cell, which organelle releases cellular energy from food?
What part of a cell makes proteins?
A solution that has more solute than a cell is _________ and will cause the cell to shrivel up.
This active transport process occurs when a cell uses energy to bring something in from the outside of the cell.
In which phase of the cell cycle is DNA replicated?
Answers:

19. #5 Describe exothermic reactions.
Are products on the left or right of the arrow in a reaction?
The molecule that an enzyme binds to is known as its __________.
Reactants bind to enzymes at the ________________.
In order to make products, all chemical reactions break or form ______.
Answers:

20. #6 **Label the reactants, products, and activation energy
1. Draw an energy diagram graph showing an exothermic reaction with no enzyme.
**Label the reactants, products, and activation energy
Answer:
X-axis should be labeled Reaction progress or time; Y-axis should be labeled Energy (1)
Exothermic means less energy in products than reactants so products side should be lower (1)
Reactants labeled on left, products labeled on right (1)
No enzyme (1)
Activation Energy Correctly labeled (1)

21. #7 **Label the reactants, products, and activation energy
1. Draw an energy diagram graph showing an endothermic reaction with an enzyme.
**Label the reactants, products, and activation energy
Answer:
X-axis should be labeled Reaction progress or time; Y-axis should be labeled Energy (1)
Endothermic means more energy in products than reactants so products side should be higher (1)
Reactants labeled on left, products labeled on right (1)
Enzyme correctly labeled (1)
Activation Energy correctly labeled (1)