Enzymes and Factors affecting Enzyme Activity

Which of the following DO NOT affect reaction rates of enzymes?

• Enzyme concentration

• Substrate concentration

• Temperature

• Pressure

Competitive inhibitors compete with substrates to bind to the _________ ______. This reduces the enzyme activity.

What is a molecule that binds to the active site to ensure the substrate can bind effectively with the enzyme?

• Catalyst

• Inhibitor

• Active site

• Cofactor

What is the optimal pH for this enzyme?

• 6

• 10

• 9

• 7

A competitive inhibitor

• binds to the allosteric site, blocking the substrate

• binds to the active site, blocking the substrate

• has a different shape than the enzyme

• lowers the activation energy of a reaction

When an enzyme tightens around a substrate, this is called:

• An awkward hug

• Induced fit

• Competitive Inhibition

• Non competitive Inhibition

As temperature increases toward the optimal level, the kinetic energy of the enzyme and substrate ________, resulting in ________ collisions.

• increases, more frequent

• increases, less frequent

• decreases, more frequent

• decreases, less frequent

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 type of macromolecules does an enzyme belong?

• Protein

• Carbohydrate

• Lipid

• Nucleic Acid