Enzymes Part 2

​Understanding the means of Enzyme vocabulary, enzyme structures and their functions

I Will...

​Review enzymes, their structure, their functions, and enzyme vocabulary.

We Will...

Win of the Day...

Enzymes

proteins that function as biological catalysts

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A catalyst is​ a substance that increases the rate of a chemical reaction.

Lets Review...

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Enzymes are named according to the reaction that they catalyse and often end in "ase"

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The substance present at the beginning of the reaction is called the substrate.

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The substrate binds to the enzyme at the Active Site

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The substance made by the reaction is called the product.​

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For Example: In saliva there is an enzyme called amylase.​

It catalyses the breakdown of starch to the complex sugar maltose.

starch ------------- ► maltose​​

In this reaction, starch is the substrate, and maltose is the product.

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The Lock and Key Mechanism

An enzyme works only when the perfect fitting substrate binds at the active site.

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The enzyme is like a lock that the substrate fits like a key.

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We say that the shape of the enzyme and the shape of the substrate are complementary to one another

Activation Energy

​Enzymes - biological catalysts, speeding up reactions in the body

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Done by lowering activation energy...​

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Activation Energy - how much energy is required for the reaction to start. ​

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Multiple Choice

A model of an enzyme and its corresponding substrate is shown. Which model best represents the molecules at the end of the reaction?

Multiple Choice

The diagram below models an enzyme breaking down a complex carbohydrate called starch. Enzymes are structures used to help chemical reactions take place, but they do not actually take part in the chemical reaction. If X represents what a starch molecule will break down into, then X could represent what biomolecule and its monomer?

• Amino Acid

• Simple Sugar

• Protein

• Fatty Acid

Multiple Choice

For an enzyme to be able to catalyze a reaction, the active site must —

• be occupied by an inhibitor

• increase the activation energy level

• have a complementary shape to the substrate

• cause the enzyme to be destroyed in the reaction

​Understanding the means of Enzyme vocabulary, enzyme structures and their functions

I Will...

​Review enzymes, their structure, their functions, and enzyme vocabulary.

We Will...

Win of the Day...

​Factors that Affect Function

1. Temperature

2. pH

3. ​Inhibitors

   1. Non-Competitive Inhibitor

   2. Competitive Inhibitor​

4. ​Enzyme Concentration

5. Substrate Concentration

6. Coenzymes and Cofactors​

Temperature & Enzymes

• Enzymes are made inactive by low temperature.

  Because they are protein molecules Enzymes are damaged by heat, high temperature.

  This is called DENATURED

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Multiple Choice

What happens when enzymes are heated to a high temperature?

• The enzymes die.
• The shapes of the enzyme are altered denature
• The enzymes' amino acid sequence changes.
• The enzymes remain the same

Temperature & Enzymes

• Enzymes work best at a particular temperature. Enzymes in the human body usually work best at about 37 °C

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Multiple Choice

What is the optimal temperature of this enzyme?

• 60

• 40

• 70

• 30

• Enzymes work best at a particular pH Some enzymes work best in acid conditions (low pH). Others work best in neutral (7 pH) or alkaline conditions (high pH) 

PH & Enzymes

Multiple Choice

What is the optimal pH for this enzyme?

• 6

• 10

• 9

• 7

​- Shape of active site can change, so substrate can no longer bind and enzyme cannot catalyze. This is denaturation. ​

Multiple Choice

Changes in pH and temperature can ___________________ an enzyme which causes it to lose its shape and affects its function.

• puncture

• denature

• double

• delete

Molecule that binds to Allosteric site - site where regulator binds

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​Causes change of shape to active site, cannot catalyze reactions

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​Non-Competitive Inhibitors

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Multiple Choice

Non Competitive Inhibitors bind to _________ to prevent enzyme from catalyzing.

• Allosteric Site

• Active Site

• Site of Photosynthesis

• Binding site

​Molecule that can bind to active site of enzyme

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Prevents enzyme from forming enzyme-substrate complexes. Stops enzyme from catalyzing​

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​Competitive Inhibitor

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Multiple Choice

Competitive Inhibitors are molecules that bind to ________ to prevent enzyme from catalyzing.

• Site of Photosynthesis

• Allosteric Site

• Active Site

• Binding Site

​Enzyme concentration increases, rate of reaction increases

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​Enzyme Concentration

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Substrate concentration increases, rate of reaction increases​

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​Substrate Concentration

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Multiple Choice

Increasing substrate concentration and enzyme concentration will _________ the rate of reactions.

• Stop

• Decrease

• delay

• Increase

Cofactors - help enzymes work at optimum reactions. Inorganic ions such as calcium or magnesium

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Coenzyme- cofactors that are organic/carbon based​. Obtains from vitamins we eat

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Cofactors and Coenzymes

Multiple Choice

Cofactors and Coenzymes both help the ________ bind to the ________.

• Substrate; Enzyme

• Substrate; Allosteric Site

• Enzyme; Product

• Product; Substrate

​Understanding the means of Enzyme vocabulary, enzyme structures and their functions

I Will...

​Review enzymes, their structure, their functions, and enzyme vocabulary.

We Will...

Win of the Day...