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What’s an Enzyme?

1. Enzymes are __________.

2. Enzymes are ___________.• Catalysts _________ chemical reactions• End in –____ (Ex: sucrase, catalase)

Without an enzyme!

With an enzyme!

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WARNING• Superman had Kryptonite

• Enzymes have1. ______________(pH)2. ______ Temperatures3. Extreme _____Temps

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Chemical Reactions

___________ → (yield) _________

Ex: Fe + O2 → rust

Energy-______________Reaction Energy-_____________ Reaction

Products

Products

Activation energy

Activation energy

Reactants

Reactants

There are 2 kinds of chemical reactions

_______________________

________________________

All chemical reactions require a certain amount of energy to get started.

- This is called the… _______________________

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Why do we need Enzymes?• Speed up rate of chemical reaction by __________

the ____________ energy (energy needed to start chemical reaction)

_________ enzyme

____________

_______ enzyme

_________ energywithout enzyme

__________Energy with enzyme

_____________

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How do ENZYMES work?1. The enzyme attaches to ___________2. The reactants that bind to the enzyme are

known as the ___________. 3. The part of the enzyme where the

substrate attaches to the enzyme is called the _________________.

4. The shape of the active site only ____ the shape of the substrate, like a _____ fits a ____. Only the correct substrate binds to the enzyme.

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Reactants/

Substrates

Enzyme

Lock-and-Key Mechanism- Enzymes can only bind to certain _________

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How do you speed up enzymes?

1. Add ______ of the enzyme.

2. ________ up the enzyme! Don’t warm it too much or it may not work anymore

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Once the enzyme and substrate are together, the enzyme holds the substrate so the _______ can occur. Once the reaction is over, the enzyme _________ the product and the enzyme can start a _______ reaction with an identical substrate.

Enzymes are ___ permanently changed or used up in reactions

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A change in the ____ of the enzyme can cause a change in the _________ of the active site, therefore changing the activity of the enzyme.

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What Affects Enzyme What Affects Enzyme Activity?Activity?

• Three factors:Three factors:

1.1. ______________Conditions______________Conditions

2.2. __________and ___________________and _________

3.3. Enzyme ____________Enzyme ____________

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1. Environmental 1. Environmental ConditionsConditions

1. Extreme1. Extreme ___________ ___________are the most are the most dangerousdangerous

- - high tempshigh temps may _________(unfold) _________(unfold) the enzyme.enzyme.

...Let's see...

2.2. pHpH (most like _____pH near _____) (most like _____pH near _____)

3.3. _______ concentration_______ concentration (salt ions) (salt ions)

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2. Cofactors and 2. Cofactors and CoenzymesCoenzymes

Inorganic substances Inorganic substances (_______, ______)(_______, ______) and _________ _________ (respectively) are sometimes needed for proper enzymatic ___________enzymatic ___________.– Example:Example:

IronIron must be present in the ____________________(a protein in red blood cells)(a protein in red blood cells) in order for it to pick up ___________.pick up ___________.

___________enzyme helpers

(inorganic)

__________cofactors

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Two examples of Enzyme Two examples of Enzyme InhibitorsInhibitors

a. a. ___________ _____________________ __________:: are chemicals that resembleresemble an enzymeenzyme’’s normal _______s normal _______and competecompete with it for the _______site_______site.

Enzyme

Competitive inhibitor

Substrate

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InhibitorsInhibitorsb.b. ____________inhibitors____________inhibitors::

Inhibitors that do not enter thedo not enter the _____ site_____ site, but bind tobind to _______ part_______ part of the enzymeenzyme causing the enzymeenzyme to ______ its _____________ its _______, which in turn

alters the active sitealters the active site.

Enzymeactive site altered

NoncompetitiveInhibitor

Substrate