Enzyme Catalysis and Function Quiz

What is the primary role of a catalyst in a chemical reaction?

• To lower the activation energy of the reaction

• To be consumed during the reaction

• To change the Gibbs free energy of the reaction

• To increase the temperature of the reaction

Which of the following is NOT a way enzymes lower activation energy?

• Increasing the entropy change

• Destabilizing the substrate's ground state

• Stabilizing the transition state

• Providing alternative reaction pathways

What is the role of the binding site in an enzyme?

• To catalyze the reaction

• To bind to substrates and orient them for catalysis

• To change the enzyme's shape

• To release the product

What is an apoenzyme?

• A type of ribozyme

• A non-protein chemical compound

• An enzyme with its cofactor

• An enzyme without its cofactor

Which of the following is true about enzyme specificity?

• Enzymes only bind specific substrates and catalyze specific reactions

• Enzymes catalyze multiple reactions simultaneously

• Enzymes produce a variety of products

• Enzymes can bind to any substrate

What is enzyme promiscuity?

• The ability of enzymes to produce waste products

• The ability of enzymes to bind to multiple substrates

• The ability of enzymes to catalyze reactions without substrates

• The ability of enzymes to change their structure

What is the main difference between the lock and key model and the induced fit hypothesis?

• Both models suggest enzymes are rigid

• Both models suggest enzymes are flexible

• The lock and key model suggests enzymes are flexible, while the induced fit hypothesis suggests enzymes are rigid

• The lock and key model suggests enzymes are rigid, while the induced fit hypothesis suggests enzymes are flexible

According to the induced fit hypothesis, how do enzymes interact with substrates?

• Enzymes break down substrates immediately

• Enzymes remain static and do not change shape

• Enzymes change shape to fit the substrate precisely

• Enzymes release substrates without binding

Which model was proposed by Emmel Fischer in 1894?

• Enzyme promiscuity model

• Induced fit hypothesis

• Lock and key model

• Conformational proofreading mechanism

What is the purpose of the conformational proofreading mechanism?

• To decrease enzyme specificity

• To enhance molecular recognition fidelity

• To increase the number of substrates an enzyme can bind

• To allow enzymes to function without substrates