Chemical Reactions and Enzymes

An enzyme speeds up a reaction by

• lowering the activation energy.
• raising the activation energy.
• releasing energy.
• absorbing energy.

In a chemical reaction, a reactant binds to an enzyme at a region known as the

• catalyst.
• product.
• substrate.
• active site. 

What are the substances that are created by a chemical reaction?

• Products

• Reactants

• Molecules

• Ingredients

The energy needed to start a reaction is called the

• activation energy

• starting energy

• promoting energy

• reacting energy

Once an enzyme has helped a reaction take place, it can then

• be reused for another reaction with the same reactants.

• be broken down.

• be stored in the cell until it is needed again.

• be used to help different reactants go through a reaction.

What type of macromolecules does an enzyme belong?

• Protein

• Carbohydrate

• Lipid

• Nucleic Acid

An enzyme fits its substrate like 

• a lock and key
• peas and carrots
• a product and reactant

What is the purpose  of an enzyme?

• give permission for the reaction
• raise activation energy
• speed up reactions
• control how many reactions occur

After the enzyme and substrate bind together and perform the reaction, what does the substrate become?

• a substrate
• an enzyme
• a product
• an active site

In the diagram, what is letter A? 

• product
• substrate
• enzyme-substrate complex
• active site