11. Refer to the figure below. нн Н `NH2 NH2 N' N- 2e-+H* R NAD+ NADH NAD+ functions as a coenzyme in many enzyme-catalyzed reactions. The changes that take place in this coenzyme are the same for all of these reactions and are illustrated in the figure. It is likely that, in these reactions, NAD+ functions as an electron acceptor (reducing agent) in redox reactions. functions as an electron donor (oxidizing agent) in redox reactions. functions as a base in acid-base catalytic mechanisms. functions as an electron donor (oxidizing agent) in redox reactions. functions as an electron acceptor (oxidizing agent) in redox reactions. +Z-

11. Refer to the figure below. нн Н `NH2 NH2 N' N- 2e-+H* R NAD+ NADH NAD+ functions as a coenzyme in many enzyme-catalyzed reactions. The changes that take place in this coenzyme are the same for all of these reactions and are illustrated in the figure. It is likely that, in these reactions, NAD+ functions as an electron acceptor (reducing agent) in redox reactions. functions as an electron donor (oxidizing agent) in redox reactions. functions as a base in acid-base catalytic mechanisms. functions as an electron donor (oxidizing agent) in redox reactions. functions as an electron acceptor (oxidizing agent) in redox reactions. +Z-

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter6: Energy, Enzymes, And Biological Reactions

Section: Chapter Questions

Problem 6TYK: Which of the following methods is not used by enzymes to increase the rate of reactions? a. covalent...

See similar textbooks

Similar questions

The Krebs cycle converts ________ through a cycle of reactions. In the process, ATP, ________, and ________ are produced. acetyl CoA; FAD, NAD acetyl CoA; FADH2; NADH pyruvate; NAD; FADH2 pyruvate; oxygen; oxaloacetate
Which of the following comparisons or contrasts between endergonic and exergonic reactions is false? Endergonic reactions have a positive ?G and exergonic reactions have a negative ?G Endergonic reactions consume energy and exergonic reactions release energy Both endergonic and exergonic reactions require a small amount of energy to overcome an activation barrier Endergonic reactions take place slowly and exergonic reactions take place quickly.
Which of the following statements about the allosteric site is true? a. The allosteric site is a second active site on a substrate in a metabolic pathway. b. The allosteric site on an enzyme can allow the product of a metabolic pathway to inhibit that enzyme and stop the pathway. c. When the allosteric site of an enzyme is occupied, the reaction is irreversible and the enzyme cannot react again. d. An allosteric activator prevents binding at the active site. e. An enzyme that possesses allosteric sites does not possess an active site.
In an enzymatic reaction: a. the enzyme leaves the reaction chemically unchanged. b. if the enzyme molecules approach maximal rate, and the substrate is continually increased, the rate of the reaction does not reach saturation. c. in the stomach, enzymes would have an optimal activity at a neutral pH. d. increasing temperature above the optimal value slows the reaction rate. e. the least important level of organization for an enzyme is its tertiary structure.
In the following graph: A represents the product. B represents the energy of activation when enzymes are present. C is the free energy difference between A and D. C is the energy of activation without enzymes. E is the difference in free energy between the reactant and the products.
When deprived of oxygen, yeast cells obtain energy by fermentation, producing carbon dioxide, ATP, and (a) acetyl CoA (b) ethyl alcohol (c) lactate (d) pyruvate (e) citrate
The enzyme directly responsible for almost all carbon fixation on Earth is (a) rubisco (b) PEP carboxylase (c) ATP synthase (d) phosphofructokinase (e) maltase
Which of the following reaction pathways is not part of the second stage of aerobic respiration? a. electron transfer phosphorylation b. acetyl-CoA formation c. Krebs cycle d. glycolysis e. a and d
Which of the following methods is not used by enzymes to increase the rate of reactions? a. covalent bonding with the substrate at their active site b. bringing reacting molecules into close prosimity c. orienting reactants into positions to favor transition states d. changing charges on reactants to hasten their reactivity e. increasing fit of enzyme and substrate that reduces the energy of activation
When two glucose molecules react to form maltose: a. the reaction represents a negative G. b. free energy had to be available to allow the reaction to proceed. c. the reaction is exothermic. d. it supports the second law of thermodynamics, which states there is tendency of the universe toward disorder. e. the resulting product has less potential energy than the reactants.
Which statement correctly describes carbon fixation? the conversion of CO2 into an organic compound the use of RuBisCO to form 3-PGA the production of carbohydrate molecules from G3P the formation of RuBP from G3P molecules the use of ATP and NADPH to reduce CO2
Which of the following is the major source of electrons that flow through the mitochondrial electron transport chain? (a) H2O (b) ATP (c) NADH (d) ATP synthase (e) coenzyme A