1. Enzyme Structure and Function

2. Chemical formulas Reactants – what you start with
Products – what you end up with
“” means “yields” or “becomes”
Glucose Fructose  Sucrose + Water
Reactants  Products

3. Unit 1: Biochemistry and Digestion
Reactions in the body
Catabolic – breaking down (CATastrophic…)
Exergonic
Releases energy
Energy-rich reactants  Energy-poor products
Anabolic – building up
Endergonic
Absorbs/requires energy
Energy-poor reactants  Energy-rich products

4. Reading an energy graph
Unit 1: Biochemistry and Digestion
Reading an energy graph

5. What are Enzymes?
Enzymes are proteins (but not all proteins are enzymes)
There are as many as 2000 different enzymes in a single cell

6. What do enzymes do?
Speed up reactions (sometimes 10 billion times faster!)
Work by lowering start up (activation) energy of a reaction

7. Enzymes are important…
in regulating chemical pathways.
for synthesizing materials needed by cells.
in catalyzing chemical reactions that release energy.

8. What do enzymes look like?

9. How do enzymes work?
Enzyme and substrate are in the same area
Enzyme grabs substrate(s) into its active site
Substrate is changed into the product(s) of reaction
Enzyme releases product(s) and returns to its original shape to be used again
hill.com/sites/ /student_view0/chapter2/ animation__how_enzymes_work.html

11. How do enzymes work?
Anabolic reactions:
Catabolic reactions:

12. Enzyme specificity Each enzyme has a specifically shaped active site
Only one substrate fits into the active site
Each enzyme only catalyzes one reaction

13. Temperature affects enzymes
Moving molecules depend on temp.
warmer = faster; colder = slower
Rate of chemical reactions depends on temperature
Faster molecules = more collisions b/w enzyme and substrate
Too much heat can destroy enzymes by causing them to lose their shape (denaturation)

14. pH affects enzyme function
Many enzymes work best at pH = 7
Enzyme shapes are influenced by the presence/absence of H+
Some enzymes work best at acidic pH!

15. Concentration of substrate influences enzyme activity
How much substrate is available can determine how quickly the enzyme can work.
The more substrate, the more likely an enzyme is to collide with substrate.

16. Demonstrating change in reaction rate with change in substrate concentration Pop It Bead Activity
In pairs:
1 is the enzyme (blindfolded!)
1 is the timer/observer
Substrate are single pop it beads
Reaction: 2 single pop its  2 pop its connected
Observer will count how much “product” is made in 10 seconds for different “concentrations of substrate”: 10 pop its, 20, 30, 40

17. Results from Pop It Activity:
How much product was made for each concentration of substrate?