Starter

1. All of the chemical reactions that take place in an organism are referred to as m_______.

2. Is this a physical or chemical reaction? How do you know?

3. Is this a physical or chemical reaction? How do you know?

#1 - Enzymes are which of the following molecules?

A. CarbohydratesB. LipidsC. ProteinsD. Nucleic Acids

#2 - Enzymes influence chemical reactions in living systems by

A. providing the substrate required for the reaction to occur

B. affecting the rate at which reactions occur C. absorbing water released when polymers are

formed D. combining with excess hydrogen to form

gaseous wastes

Enzyme Animation

• Why can an enzyme be reused?• They are not changed or used up after a

reaction!

Q #5 - Which answer do you most agree with? Why?

A. There was no reaction between the liver and the vinegar because vinegar isn’t an enzyme.

B. There was no reaction because vinegar cannot be broken down.

C. There was no reaction because vinegar doesn’t break an enzyme down.

D. There was no reaction because the enzymes in liver do not work to break down vinegar.

Enzymes work on a specific substrate!

What makes them specific?

Do they look the same?

Hydrogen peroxide Vinegar

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_enzymes_work.html

Lock and Key Hypothesis

http://www.northland.cc.mn.us/biology/Biology1111/animations/enzyme.html

Enzyme and substrate fit together perfectly, like a lock and key!

WHAT KINDS OF THINGS MIGHT IMPACT HOW WELL AN ENZYME WORKS?

Enzymes are Proteins…

• http://www.sumanasinc.com/webcontent/animations/content/proteinstructure.html

DENATURING AN ENZYME…

HEAT CHANGE IN pH

result in…

DENATURING…

http://www.lew-port.com/10712041113402793/lib/10712041113402793/Animations/Enzyme_activity.html

Changes the shape! How?

-too much heat-adding acid or base to change PH

How does a catalyst work?

Activation energy = energy needed to start a chemical reaction

What do enzymes do to activation energy?

A + B AB

#3 – What do enzymes do to activation energy?

A. Increase itB. Decrease itC. Keep it the same

#4 – So, which do you think would happen faster?A. Red line, because it requires more energy to get started. B. Red line, because it requires less energy to get started. C. Blue line, because it requires more energy to get started. D. Blue line, because it requires less energy to get started.

Enzymes increase the rate of a reaction!• They work by lowering the activation energy

needed to start the reaction!

Q #6 – If an enzyme is like a lock, what would represent the active site?

A. The key, because it fits the lockB. The combination, because it is used to open

the lock.C. The key hole, because that’s where the key

fits.D. The lock itself, since it’s the enzyme.

Q #7 – An enzyme that breaks down protein will not act upon starch. This fact is an indication that enzymes are

A. proteins B. specific C. catalysts D. synthetic

WHAT ELSE?????

THINK ABOUT THE PAPERASE LAB!

Q #8 – At high temperatures, the rate of enzyme action decreases because the increased heat

A. changes the pH of the system B. alters the active site of the enzyme C. neutralizes the acids and bases in the systemD. increases the amount of the enzyme

Q #9 – Which environmental condition would most likely have the LEAST effect

on the rate of an enzyme reaction?

A. the pH of the solution B. the temperature of the solution C. the amount of enzyme present D. the amount of light present

THE REACTIONS WITHIN CELLS GENERALLY INVOLVE THE BUILDING OR THE BREAKDOWN OF COMPLEX

COMPOUNDS.

Synthesis and Decomposition

Anabolic reactions

Build compounds. (SYNTHESIS)

Energy is stored during these reactions.

Catabolic reactions

Break down compounds. (DECOMPOSITION)

Energy is released during these reactions.