Open to your Homework Any questions?

2

Carbohydrates Lipids ProteinsFunctionExamples

Monomer Structure (illustrate)PolymerPolymerization reaction

Dietary Sources

Test for presence?

Other?

Enzymes

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CH 4 …demonstrate an understanding of the structures & functions of biological moleculesI can…

- describe the chemical structure of enzymes

- describe the mechanisms of various enzymes

We are learning to…

Enzymes• biological catalysts • Are proteins speed up chemical reactions

without being consumed

Build an Enzyme.

Enzyme Action• enzymes bind to specific reactants called

substrates • substrates bind to active sites on enzymes,

forming the enzyme-substrate complex

Enzyme-Substrate Complex

Induced-Fit Model

• the “lock and key” hypothesis - early model

• in the “induced-fit” model, the enzyme alters its shape to better “fit” substrate

Lock and Key

Induced Fit

Example: Sucrase

What reactions do these enzymes catalyze?

lactase • breaks down lactose (sugar found in milk) amylase • breaks down starch (in saliva & intestine) Alcohol Dehydrogenase • breaks down alcohol (in the stomach and liver)

Cofactors and CoenzymesSome enzymes require: • cofactors - non-protein molecules or inorganic

ions (often metals) – Bind to enzymes to promote function

• coenzymes - organic molecules (derived from vitamins or minerals) – often act as shuttles delivering molecules

from one enzyme to another. (NAD+)

Cofactors

Factors AffectingRate of Enzyme Activity

• temperature • pH • enzyme concentration • substrate concentration

15

How would you set up a lab to determine…

1. If temperature affected amylase activity?

or

2. If pH affected amylase activity?

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We are learning to…CH 3 …investigate the chemical structures, functions,

and chemical properties of biological moleculesI can…

- plan a lab related to a cell process

- conduct a lab related to a cell process

- report results in an appropriate format