110 likes | 132 Views
How enzyme function. Chemical reaction. The cells carries out many chemical reactions. A + B C +D reactants products All the reactions that occur in a cell have an enzyme. Enzymatic action.
E N D
Chemical reaction • The cells carries out many chemical reactions. A + B C +D reactants products • All the reactions that occur in a cell have an enzyme.
Enzymatic action • Enzymes are organic catalysts that speed metabolic reactions. • Most of the enzymes are proteins. • The reactants in an enzymatic chemical reaction are called substrates. E + S ES E + P
Enzymes have specific shape accommodating the shapes of their substrate. • Enzymes can be used over and over again. Active site
Catalase • Catalase speeds the breakdown of hydrogen peroxide to water and oxygen 2H2O2 2H2O + O2 catalase
Factors affecting enzyme activity • Temperature • Concentration (of enzyme or substrate) • pH
Temperature • Cold (ice bath)— slow chemical reaction • Warm— speed chemical reaction • Hot (boiling water bath)— enzyme denature
Concentration (of enzyme or substrate) • Low—slower chemical reaction • High— faster chemical reaction
pH • pH<7 acidic • pH=7 neutral • pH>7 alkline • Each enzyme— optimum pH speed the reaction best • Low / high—affects hydrogen bonding and the structure of enzyme, reduced activity
Experiments • 1. Catalase Activity: what does the height of the bubble column mean? what’s the function of catalase? page 59 • 2. Effect of Temperature: finish table 5.2 page 60 • 3. Effect of Enzyme Concentration: finish table 5.3 page 61 • 4. Effect of pH on Enzyme Activity: finish table 5.4 page 62