Đề 10 – Bài tập, đề thi trắc nghiệm online Hóa sinh enzyme

A A. The substrate inhibits the enzyme. B B. The product of a pathway inhibits an enzyme early in the pathway. C C. An activator molecule enhances enzyme activity. D D. Enzyme concentration is increased to enhance product formation.

A A. Covalent modification of the enzyme. B B. Binding of regulatory molecules at a site other than the active site. C C. Direct competition for the active site. D D. Irreversible denaturation of the enzyme.

A A. Determine the primary structure of an enzyme. B B. Linearize the Michaelis-Menten equation for easier determination of Km and Vmax. C C. Measure the enzyme's molecular weight. D D. Identify the active site of an enzyme.

A A. It involves irreversible enzyme inhibition. B B. It suggests the active site is flexible and changes shape upon substrate binding. C C. It only applies to enzymes with multiple substrates. D D. It describes enzyme denaturation.

A A. Coenzyme. B B. Holoenzyme. C C. Zymogen. D D. Competitive inhibitor.

A A. pH 2 (highly acidic). B B. pH 7 (neutral). C C. pH 10 (highly alkaline). D D. pH 14 (extremely alkaline).

A A. The enzyme changes shape to accommodate the substrate. B B. The active site is rigid and perfectly complementary to the substrate shape. C C. The enzyme and substrate bind randomly. D D. The substrate modifies the enzyme structure after binding.

A A. Substrate specificity. B B. Primary structure. C C. Three-dimensional conformation. D D. Molecular weight.

A A. Increases Km, decreases Vmax. B B. Decreases Km, increases Vmax. C C. Increases Km, no change in Vmax. D D. No change in Km, decreases Vmax.

A A. Enzymes that catalyze different reactions but have similar structures. B B. Different enzymes that catalyze the same reaction but have different properties. C C. Enzymes that are active in their zymogen form. D D. Enzymes that are irreversibly inhibited.

A A. Competitive inhibition. B B. Non-competitive inhibition. C C. Covalent modification for enzyme regulation. D D. Enzyme denaturation.

A A. Allosteric site. B B. Active site. C C. Competitive site. D D. Non-competitive site.

A A. Active enzymes that require cofactors. B B. Inactive precursor forms of enzymes. C C. Enzymes that catalyze reversible reactions. D D. Enzymes that are only active at low temperatures.

A A. Their molecular weight. B B. The type of reaction they catalyze. C C. Their cellular location. D D. Their subunit composition.

A A. Increasing the activation energy of a reaction. B B. Decreasing the activation energy of a reaction. C C. Increasing the temperature of the reaction. D D. Decreasing the temperature of the reaction.

A A. Increases Km, decreases Vmax. B B. Decreases Km, increases Vmax. C C. Increases Km, no change in Vmax. D D. No change in Km, decreases Vmax.

A A. Competitive inhibitor. B B. Non-competitive inhibitor. C C. Cofactor. D D. Substrate.

A A. The maximum rate of an enzyme-catalyzed reaction. B B. The substrate concentration at which the reaction rate is half of Vmax. C C. The equilibrium constant for enzyme-substrate binding. D D. Independent of substrate concentration.

A A. Binding to the enzyme at a site other than the active site. B B. Binding to the active site and preventing substrate binding. C C. Decreasing the Vmax of the enzyme. D D. Increasing the Km of the enzyme, but not affecting Vmax.

A A. The active form of an enzyme with its cofactor. B B. The inactive protein component of an enzyme, lacking its cofactor. C C. An enzyme that catalyzes reversible reactions. D D. An enzyme with multiple active sites.

A A. Bind only to the enzyme-substrate complex. B B. Bind irreversibly to the active site. C C. Bind to a site other than the active site, altering enzyme conformation. D D. Increase the enzyme's affinity for the substrate.

A A. Iron (Fe2+). B B. Zinc (Zn2+). C C. Nicotinamide adenine dinucleotide (NAD+). D D. Chloride (Cl-).

A A. The inactive protein component of an enzyme. B B. The enzyme without its substrate. C C. The active form of an enzyme, including its cofactor. D D. An enzyme that only functions at high temperatures.

A A. They are highly specific for their substrates. B B. They are consumed during the reaction. C C. They increase the rate of chemical reactions. D D. They are proteins (mostly).

A A. Joining of two molecules coupled with ATP hydrolysis. B B. Transfer of functional groups. C C. Cleavage of bonds by means other than hydrolysis or oxidation. D D. Reactions involving electron transfer.

A A. Substrate concentration. B B. Enzyme concentration. C C. Product concentration. D D. Gravitational force.

A A. Oxidation-reduction reactions. B B. Transfer of functional groups. C C. Hydrolysis reactions. D D. Isomerization reactions.

A A. The substrate concentration at half-maximal velocity. B B. The Michaelis-Menten constant. C C. The maximum rate of reaction when the enzyme is saturated with substrate. D D. The initial rate of reaction.

A A. Protein components of enzymes. B B. Organic molecules that bind tightly to enzymes. C C. Non-protein chemical compounds required for enzyme activity. D D. Enzyme inhibitors.

A A. Vmax. B B. Km. C C. Km/Vmax. D D. 1/Vmax.