EnzymesEnzymes

EngageEngage

• What happens if the gall bladder is blocked?• Can you live without a gall bladder?• What do you think would happen to the digestive

process if your stomach had a neutral pH?• What if your stomach had a basic pH?• If you have an abnormal body temperature, what

do you think the overall affect to digestion would be?

ExploreExplore

• Exploration 1• A Study of Biochemical Reactions• You will observe the activity of an enzyme

in two substances, both of which break down hydrogen peroxide. One substance is plant tissue, potato. The other is animal tissue, liver. Both are sources of the enzyme, catalase, an organic compound.

• Exploration 2

• Toying with Enzymes

ExplainExplain

• What is an enzyme?

• A protein that speeds up a chemical reaction without being destroyed.

• Catalyst

Why do We Need Enzymes?Why do We Need Enzymes?

• Most chemical reactions in the cell take too long to complete on their own.

• A catalyst (enzyme) is needed to speed up these reactions.

EnzymesEnzymes

• Catalytic proteins: change the rate of reactions w/o being consumed

• Activation Energy: the E required to break bonds

• Substrate: enzyme reactant

• Active site: pocket or groove on enzyme that binds to substrate

How Do Enzymes Work?How Do Enzymes Work?

DO NOT WRITE• Enzymes are used by the

cell to lower the activation energy needed to start a chemical reaction.

• This is accomplished by binding to the reactants.

• They will then twist or bend the material lowering the energy needed to split it.

An Enzyme SystemAn Enzyme System

• Active site - specific for the object it will hold, called the substrate.

• The enzyme system is the enzyme and substrate combined.

Enzyme ReactionEnzyme Reaction

Enzyme FactsEnzyme Facts

• Enzyme are Proteins.

• DECREASE the activation energy of a reaction.

• Specific to the substrate they bind.

• Induced Fit Model

• They can be reused.

How Enzymes WorkHow Enzymes Work

QuickTime™ and aCinepak decompressor

are needed to see this picture.

Review of Digestive EnzymesReview of Digestive Enzymes

• Why do we need enzymes to help us digest out food?– It would take to long without them. They act as

a catalyst to speed up the digestive process.

• What macromolecules to digestive enzymes act upon?– Carbohydrate, Lipids, Proteins, Nucleic Acids

• Can you name three digestive enzymes?

Carbohydrate DigestionCarbohydrate Digestion

• Monomers-small molecules that can be linked to make larger molecules

• Monosaccharide (single sugar)• Disaccharide (double sugar)• MALTASE, LACTASE, SUCRASE

– Enzymes that digest Disaccharides

Fat (Lipid) DigestionFat (Lipid) Digestion

• Bile from gall bladder emulsifies fat.• LIPASE- enzymes that digests lipids

Protein DigestionProtein Digestion

• TRYPSIN and CHYOTRYPSIN – enzymes that break bonds next to specific amino acids

• Carboxypeptidase – splits off one amino acid at a time. Works on the carboxyl group.

• Aminopeptidase- works in the opposite direction.• ENTEROKINASE-hormone that activates these

enzymes.

ElaborateElaborate

• Investigating Digestive Process

• Science Kit and Boreal www.sciencekit.com

• In this lab, you will understand the actions of different enzymes in your own body.