Which statement about enzyme catalyzed reactions is NOT true? Show
Features of Enzyme Catalyzed ReactionsEnzymes are biological catalysts. Catalysts lower the activation energy for reactions. The lower the activation energy for a reaction, the faster the rate. Thus enzymes speed up reactions by lowering activation energy. Many enzymes change shape when substrates bind. This is termed "induced fit", meaning that the precise orientation of the enzyme required for catalytic activity can be induced by the binding of the substrate. Enzymes have active sites. The enzyme active site is the location on the enzyme surface where substrates bind, and where the chemical reaction catalyzed by the enzyme occurs. There is a precise substrate interaction that occurs at the active site stabilized by numerous weak interactions (hydrogen bonds, electrostatic interactions, hydrophobic contacts, and van der Waals forces). Enzymes form complexes with their substrates. The binding of a substrate to an enzyme active site is termed the "enzyme-substrate complex." A generic equation for complex formation is as follows: Enzymes do not: Change the equilibrium constant for a reaction. Keq depends only on the difference in energy level between reactants and products. Change ΔG for a reaction. As shown in the graphs above, enzymes only lower activation energy, but do not change the difference in energy levels between reactants and products. Convert a nonspontaneous reaction into a spontaneous reaction.
The Biology Project Department of Biochemistry and Molecular Biophysics University of Arizona Revised: October 2004 Contact the Development Team http://www.biology.arizona.edu Which of the following statements best helps explain the reaction of an enzyme?Which of the following statements best helps explain the reaction specificity of an enzyme? The shape and charge of the substrates are compatible with the active site of the enzyme.
Which of the following statements best helps explain the reaction specificity of hexokinase quizlet?Which of the following statements best helps explain the reaction specificity of hexokinase? Glucose has the right shape and charge to cause hexokinase to undergo a structural change needed for catalysis, whereas water does not.
Which of the following will increase the reaction rate of an enzyme reaction quizlet?increasing enzyme concentration will increase the rate of reaction, as more enzymes will be colliding with substrate molecules.
Which of the following statements best describes enzyme function quizlet?Which of the following statements best describes enzyme function? Enzymes increase the rate of chemical reactions by lowering activation energy barriers.
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