1. Enzymes

2. All of the chemical reactions in a cell makes up the cell’s Metabolism
2 main chemical reactions necessary for life
Photosynthesis = the formation of glucose in plants
Respiration = the formation of ATP from breaking down glucose
In order for a reaction to begin it must, gain a certain amount of energy called activation energy

3. Most chemical reactions occur too slowly (because of the high activation energy) to be useful to living organisms
Special proteins (enzymes) act as catalyst to speed up a reaction by lowering its activation energy
Does not increase the production of the product
Does not get used or changed in the reaction

4. Enzymes…
Are specific and will only bind to specific molecules (lock-and-key)
Are reusable
Enzymes are usually named by their substrate (the reactant they bind to) and usually end in –ase
-Sucrase
-Lactase
-Maltase

5. Enzyme
Substrate
Joins

6. The region of an enzyme where the substrate binds is called the active site.

7. Once the substrate binds to the enzyme, an enzyme-substrate complex is formed
The bonds of one substrate are broken or bonds are created between two substrates
The products are produced
Video Clip

8. Enzyme Activity
Factors such as pH and temperature can affect enzyme activity
Each enzyme is only functional under certain conditions
Changing the pH or temperature may cause changes in the shape of the enzyme called denaturing
This enzyme will no longer bind to its substrate

9. Copy down & answer the questions below.
What is the function of an enzyme?
2. What type of organic compounds are enzymes?
3. What substance takes part in an enzymatic reaction but is unchanged by the reaction?
4. Sucrase is an enzyme that breaks sucrose down into glucose and fructose. What happens to the chemical bonds in sucrose when it binds to the enzyme sucrase?
5. What could cause a change in the shape of an enzyme? Would the enzyme still work properly? Why or why not?

10. Homework
Enzyme Notes - Notes assignment # 1