Biochemistry I Module of the MCAT Self Prep eCourse: Lesson 3: Enzyme Kinetics (Pro)

Biochemistry I Module of the MCAT Self Prep eCourse: Lesson 3: Enzyme Kinetics (Pro) Biochemistry I Module of the MCAT Self Prep eCourse: Lesson 3: Enzyme Kinetics (Pro) Biochemistry I Module of the MCAT Self Prep eCourse: Lesson 3: Enzyme Kinetics (Pro) Lesson 3: Enzyme Kinetics Lesson 3: Enzyme Kinetics Write the rate law for the following reaction: A+B -> AB Rate= k [A][B] Rate is the change in concentration per unit time. k is the rate constant (depends on the reaction). [A] and [B] are the concentrations of reactants A and B. In Michaelis-Menten Kinetics experiments, which of the following is assumed to be true? I. Substrate concentration is constant. II. Increasing the Enzyme concentration will not change Vmax. III. The enzymes are saturated at Vmax. (A) I Only (B) III Only (C) I and II Only (D) I, II, and III (B) III Only In Michaelis-Menten Kinetics experiments: - ENZYME concentration is held constant as we increase the substrate concentration. - If you were to increase the enzyme concentration, the Vmax would increase. - The enzymes are saturated at Vmax. In Michaelis-Menten Kinetics experiments, which of the following is assumed to be true? I. Our Solutions are behaving ideally. II. Our constants ([E] and k) are not changing during the experiment. III. Substrate can be converted into product with or without the enzyme. (A) I Only (B) III Only (C) I and II Only (D) I, II, and III (C) I and II Only In Michaelis-Menten Kinetics experiments, we assume that: - Our Solutions are behaving ideally. - Our constants ([E] and k) are not changing during the experiment. - Substrate CANNOT be converted into product without the enzyme. How can we increase the rate of a reaction assuming the rate constant (k) is constant? I. Increase Substrate Concentration II. Increase Enzyme Concentration III. Increase Mixed Inhibitor Concentration (A) I Only (B) I and II Only (C) II and III Only (D) I, II, and III (B) I and II Only We can increase the rate of reaction by increasing the substrate or enzyme concentration. Adding any type of inhibitor will not increase the rate of a reaction. True or false? Adding more catalyst after a catalytic amount has already been added will increase the rate of reaction. False. Adding more catalyst after a catalytic amount has already been added will NOT AFFECT the rate of reaction. You only need a small amount ("a catalytic amount") of catalyst for it to do its job. Adding more will not do anything. What does it mean if the rate of reaction has reached maximum velocity (Vmax)? (A) There are more products than reactants. (B) The substrates are no longer able to get any closer to the enzymes. (C) The substrates are no longer able to get in any better of an orientation. (D) The enzymes no longer have available active sites. (D) The enzymes no longer have available active sites. When the rate of reaction reaches Vmax, it means that the enzymes are saturated and will not be able to react any more quickly since all active sites are filled up with substrates.