ENZYMESA Special Type of Protein

A. Enzymes Almost all enzymes are protein

catalysts made by living organisms (like us!)→Catalysts can change rate or speed of chemical reaction without being consumed or destroyed

+catalaseH2O2Hydrogen peroxide

(liq)

H2OWater (liq)

O2Oxygen

(gas)

(found in human and bacterial cells)

+

→Speeds up favorable reactions by reducing activation energy needed for a chemical reaction to beginoActivation energy: energy needed to start chemical reaction (EA)♦Example: to get boulder rolling down the hill, must first push it = activation energy –Activation energy MUST be supplied for all chemical reactions to occur

Enzymes Create Energy Needed to Run Reaction

+EA

H2O2 H2O O2

→Enzyme acts on chemical called substrate which binds to enzyme, causing chemical reaction to take place ♦ involved in almost all metabolic

or chemical processes

Catalase Example+catalaseH2O2

Hydrogen peroxide

(liq)

H2OWater (liq)

O2Oxygen

(gas)

SUBSTRATE

ENZYME

PRODUCT

Enzyme/Substrate = Lock/Key

Only ONE enzyme attaches to ONE specific substrate to power the reaction – just like a lock, it never gets destroyed.

lock enzyme

keysubstrate

♦ any factor that changes shape of enzyme can affect enzyme activity:1. substrate concentration

B. Enzyme Activity = Speed of Reaction

2. temperature range◦ Each enzyme works best at a specific temperature.

Temperature extremes will denature or destroy an enzyme.

3. pH range>out of range will change enzyme, reducing effectiveness

http://www.phschool.com/science/biology_place/labbench/lab2/ph.html

The END

HOMEWORK◦p. 42 DATA LAB #1-5◦P. 42 #1-6