Physiology Quiz - Michaelis-Menten Kinetics - Part 1

Michaelis-Menten kinetics is used to describe the rate of a reaction catalyzed by an enzyme as a function of the substrate concentration. This type of analysis is also commonly used to describe the rate of transporter-mediated translocation of ions and molecules across biological membranes. Test your basic knowledge of Michaelis-Menten kinetics by taking this simple quiz.

(1) The K_{m} (Michaelis constant) of an enzyme-catalyzed rection:

(2) Which of the following equations is the Michaelis-Menten equation?

(3) Which of the following equations is the Hill equation?

(4) A higher numerical value of the Michaelis constant (K_{m}) indicates a higher enzyme/transporter affinity for its substrate.

(5) Assume that the reaction catalyzed by an enzyme follows Michaelis-Menten kinetics. The substrate concentration (K_{m}, Michaelis constant) needed to reach 50% of the maximum reaction velocity (V_{max}) is 25 μM. What substrate concentration is required to obtain at least 95% of the maximum reaction velocity?

(6) Assume that the reaction catalyzed by an enzyme follows Michaelis-Menten kinetics. If at a substrate concentration of 100 nM, the reaction proceeds at 98% of the maximum reaction velocity (V_{max}), what is the Michaelis constant (K_{m}) for this substrate. K_{m} is the substrate concentration needed to reach 50% of V_{max}.