Enzyme Activity and Function Quiz

Be able to read and identify the different aspects of a free energy graph of a chemical reaction and how an enzyme affects it. Which of the following statements is true?

• Enzymes increase the activation energy of a reaction.

• Enzymes decrease the activation energy of a reaction.

• Enzymes have no effect on the free energy of a reaction.

• Enzymes change the equilibrium constant of a reaction.

Know the effects of temperature and pH on enzyme activity. Which of the following explains why some enzymes can work best at higher optimal temperatures or pHs?

• Enzymes are proteins that can denature at extreme temperatures or pH levels.

• Some enzymes have evolved to function optimally in specific environments.

• Higher temperatures always increase enzyme activity.

• All enzymes work best at neutral pH.

Know the relationship between enzymes, activation energy, and the speed of a reaction.

• Enzymes increase activation energy and slow down reactions.

• Enzymes decrease activation energy and speed up reactions.

• Enzymes have no effect on activation energy or reaction speed.

• Enzymes increase activation energy and speed up reactions.

Know how enzymes work including the induced fit where enzymes fit snugly around the substrate “clasping handshake”.

• Induced fit

• Lock and key model

• Competitive inhibition

• Non-competitive inhibition

Know how enzymes work including the substrate, which is the substance enzyme acts upon.

• Substrate

• Inhibitor

• Catalyst

• Product

Know how enzymes work including the enzyme-substrate complex, which is when the enzyme binds to its substrate.

• Enzyme-substrate complex

• Enzyme-product complex

• Substrate-enzyme complex

• Product-substrate complex

Know how enzymes work including whether or not they get degraded during reactions. Enzymes don’t get degraded during the reactions.

• Don’t get degraded

• Get degraded

• Are consumed

• Are permanently altered

Know how enzymes work including the type of macromolecule they are.

• Proteins

• Carbohydrates

• Lipids

• Nucleic acids

Know how to read graphs of relative activity of enzymes vs pH or temperature to tell when the enzyme is at its highest activity.

• At the peak of the graph

• At the lowest point of the graph

• At the beginning of the graph

• At the end of the graph

Know the difference between a cofactor and a coenzyme.

• Cofactors are non-protein molecules that assist enzymes, while coenzymes are a type of cofactor that are organic molecules.

• Cofactors are proteins that assist enzymes, while coenzymes are inorganic molecules.

• Cofactors and coenzymes are both proteins that assist in enzyme function.

• Cofactors are organic molecules, while coenzymes are inorganic molecules.