Understanding Allosteric Enzymes

What is a characteristic feature of allosteric enzymes?

• They consist of a single polypeptide unit.

• They have multiple active sites.

• They are always in an active state.

• They do not change shape.

How does an activator affect an allosteric enzyme?

• It stabilizes the inactive state.

• It prevents substrate binding.

• It deactivates the enzyme.

• It stabilizes the active state.

What role do non-competitive inhibitors play in enzyme activity?

• They bind to the active site.

• They increase substrate affinity.

• They change the enzyme's shape.

• They activate the enzyme.

What is an example of a protein that exhibits cooperativity?

• Insulin

• Collagen

• Myoglobin

• Hemoglobin

How does the binding of one oxygen molecule affect hemoglobin?

• It decreases the affinity for more oxygen.

• It has no effect on other subunits.

• It increases the likelihood of other subunits binding oxygen.

• It causes the hemoglobin to release all oxygen.

What happens when oxygen is offloaded from hemoglobin?

• It increases the chance of other subunits binding oxygen.

• It decreases the likelihood of other subunits releasing oxygen.

• It has no effect on other subunits.

• It increases the chance of other subunits releasing oxygen.

What is the main function of allosteric inhibitors?

• To enhance enzyme activity.

• To stabilize the inactive state.

• To increase substrate binding.

• To stabilize the active state.

What is the effect of cooperative binding on enzyme activity?

• It has no effect on enzyme activity.

• It enhances the enzyme's ability to bind more substrate.

• It causes the enzyme to become inactive.

• It decreases the enzyme's efficiency.

How can a substrate act in relation to an allosteric enzyme?

• As an inhibitor

• As a competitor

• As an activator

• As a deactivator

What should be the focus when studying allosteric enzymes for assessments?

• Basic understanding of activators and inhibitors

• Detailed mechanisms of substrate acting as activators

• Memorizing all enzyme structures

• In-depth study of allosteric sites