Chemical reactions involve forming or breaking of chemical bonds Na + Cl NaCl Reactants Products The...

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Energy and Chemical Reactions

OBJECTIVES: RELATE ENERGY AND CHEMICAL REACTIONS DESCRIBE THE ROLE OF ENZYMES

DO NOW: Take out your homework. Then…is cellulose a monosaccharide or polysaccharide? Where is it found?

HOMEWORK: finish concept 5 packet Review sheet due Moday.

Chemical reactions involve forming or breaking of chemical bonds

Na + Cl NaCl

Reactants ProductsThe chemicals involved The chemicals at the start of a reaction produced at the

end of a reaction

Chemical ReactionsNeed help to get started

Ex. Match starts a fireActivation Energy

Energy required to get a chemical reaction started

Activation Energy

REACTANTSPRODUCTS

ACTIVATIONENERGY

A catalyst can reduce the activation energy needed to start a reaction.Speeds up the reactionNot consumedReusable

Chemical reactionsCatalysts help chemical reactions happen

fasterWork by decreasing the amount of

activation energy required to get a chemical reaction started

Some reactions absorb energy while others release energy.

EnzymesProteins that act as catalysts to control

chemical reactionsAre NOT changed when they perform task

Used again and again

Specificity Fit like a “lock and key”

VERY specificEach has only ONE reaction it can helpShape determines function

SUBSTRATE

ENZYME-SUBSTRATE COMPLEX

PRODUCTSENZYMEUnchanged& Reusable

ENZYME

ACTIVESITE

Factors that effect enzymesConditions that are too hot or too acidic

cause proteins to unwind or denature

Denaturing changes the shape of the active site Enzyme can’t bind to substrate

Homeostasis (temp and pH) important for enzyme function

Naming enzymesMost end in _______-aseBeginning tells what it doesExamples:

Lipase-breaks down lipidsSucrase-breaks down sucroseDNA polymerase-polymerizes DNALactase-breaks down lactoseProtease-breaks down proteins

OBJECTIVES: RELATE ENERGY AND CHEMICAL REACTIONS DESCRIBE THE ROLE OF ENZYMES

DO NOW: Take out your homework. Then…Where are electrons, protons, and neutrons located? How many protons does an atom with an atomic number of 9 have? Neutrons?

HOMEWORK: Review sheet, test Tuesday

Warm Up: Review notes quietly for 5 minutesHomework: Read Section 7.1 and complete