CHEMICAL REACTIONS

AND ENZYMES

Chemical reaction: is a process that

changes, or transforms, one set of chemicals into another

Two Parts Of A Chemical Reaction

Reactants: The elements or compounds

that enter into a chemical reaction

Products: The elements or compounds

produced by a chemical reaction

Reactants Products

Reactant + Reactant → Product

+

Reactant → Product + Product

+

How do we get these reactions started???

Activation Energy: The energy that is needed to get a reaction started

Enzymes are biological catalysts

Catalysts: speed up the chemical reactions by lowering the activation energy

Enzymes: are proteins that act as a biological catalyst- Enzymes speed up reactions that take place in cells

Enzymes animation http://highered.mcgraw-

hill.com/sites/0072495855/student_view0/chapter2/animation__how_enzymes_work.html

Another word for Reactant is SUBSTRATE

enzyme

Reactant + Reactant → Product

OR

enzyme

Reactant → Product + Product

Each enzyme has certain Optimal

Conditions in which it functions best

…but, enzymes don’t always function

properly

Denaturation: a structural change in

macromolecules caused by extreme

conditions—they loose their shape!

These conditions consist of:

Temperature

pH

Heavy metals

Alcohol

DENATURATION

Temperature

pH

Heavy metals

Alcohol

ENZYMES Review UNDERSTANDING THE ENZYME CATALASE

http://www.lpscience.fatcow.com/jwanama

ker/animations/Enzyme%20activity.html

Chemical Reaction:

Hydrogen peroxide Water + Oxygen

2 (H2O2) 2(H2O) + (O2)

Reactant catalase Products

Enzymes Pre-lab

UNDERSTANDING THE ENZYME CATALASE

Questions for Investigation:

What will happen to the activity of catalase if we change environmental conditions?

What conditions can we change?

Experimental Design—

Independent Variable

Dependent Variable

Control

Constants

Hypothesis

LAB DEMO

Observe the procedure and answer the

questions on your DATA sheet.

What is the liquid present on each one of

the four tubes?

What will be added to each tube?

LAB DEMO Record your observations in table 1 for each

of the tissues Rate of the reaction: how rapidly the solution

bubbles. 0 = No reaction 1 = slow reaction … 5 = very fast Part II: Boiled liver. Repeat procedure Part III: pH effect. Repeat procedure

CONCLUSIONS

Living tissue contain catalase

Catalase present in living tissues brakes down hydrogen peroxide into

____________ and ____________

Enzymes are reusable

Enzymes are affected by high

temperature s and pH (Denatured)

HOW MUCH DID YOU LEARN ABOUT ENZYMES?

Write down one page (2-3 paragraphs) summarizing what you learned about enzymes and why they are important