a) How do enzymes catalyze (increase the rate of) reactions? b) What does it mean that enzymes are “substrate specific”? c) How are they usually name

In a Lineweaver-Burk graph, the place where the line crosses the Y-axis represents:  a)  Km   b)  Vmax   c) 1/Km    d)  1/Vmax Which coenzyme is most often used in dehydrogenation reactions of the type –CH2CH2- = -CH=CH- ? a) NAD   b)   FAD   c)   NADP    d)  FMN Which one of these transports fructose? A) GLUT-2 b)  GLUT-3   c)   GLUT-4    d)   GLUT-5 The pyruvate dehydrogenase complex converts pyruvate to which molecule? A) oxaloacetate b)   glycogen   c)  acetyl-CoA  d)  citrate The pyruvate dehydrogenase complex produces how many ATP molecules at the substrate level? A) 0   b)   1   c)   3   d)  4 The pyruvate dehydrogenase complex produces how many ATP molecules indirectly via oxidative phosphorylation per glucose molecule? A)  1   b)  3    c)  5  d)  over 30

Which of the following is a type of irreversible enzyme inhibitor A) Mechanism-based (suicide) inhibitor B) Non-competitive inhibitor C) Uncompetitive inhibitor OD) Competitive inhibitor 8

2. Enzymes A) have highest affinity for the substrate B) have highest affinity for the product C) have highest affinity for the transition state D) None of the above Briefly explain:

23.

1. Enzymes A) tilt the reaction equilibrium in favor of product formation B) tilt the reaction equilibrium in favor of reactant formation C) reduce AG D) None of the above Briefly explain:

In competitive inhibition A) a molecule competes for the allosteric site on an enzyme B) two proteins combine C) a molecule completes for the active site on an enzyme D) activation energy is reduced

Which of the following describes a purpose for the function of phosphoglucoisomerase? a) allows for phosphorylation for trapping the molecule in the cell b)promotes substrate level phosphorylation and formation of ATP c) allows formation of a primary alcohol necessary for the next step of phosphorylation d)facilitates epimerization, the change in stereochemistry at one chiral carbon

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Which of the following statements is true concerning thermodynamics of reactions within a cell? a) Spontaneous reactions always consume energy b) Unfavorable reactions can be coupled to nonspontaneous reactions c) Compartmentalization can be used to drive up the concentration of substrates to force a reaction to occur d) All important reactions are spontaneous