Question

Which of the following statements describes NAD+?
A. NAD+ is oxidized by the action of hydrogenates.
B. NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle.
C. NAD+ can donate electrons for use in oxidative phosphorylation.
D. In the absence of NAD+, glycolysis can still function.
E. NAD+ has more chemical energy than NADH.

Answer 1

Which of the following statements describes NAD+?
A. NAD+ is oxidized by the action of hydrogenates.
B. NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle.
C. NAD+ can donate electrons for use in oxidative phosphorylation.
D. In the absence of NAD+, glycolysis can still function.
E. NAD+ has more chemical energy than NADH.

Answer 2

NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle
NAD+ is reduced by the action of hydrogenases..

NAD+ picks up hydrogens from the link reaction and Kreb's cycle, bringing them to the elctron transfer chain. The NADH (because of the picked uphydrogen) breaks down into NAD+, a hydrogen ion and an excited electron (electron with a lot of energy).

Answer 3

Best is option B.
A.
For reaction between two one-carbon compounds :
CH3OH + NAD+ + dehydrogenase ----> CH2O + NADH + H+ + dehydrogenase
(that is, the removal of two hydrogen atoms and their acceptance by NAD+)
B.
During glycolysis, 2 ATP molecules are used to phosphorylate and activate compounds that will eventually become converted to pyruvate and two hydrogenatoms are removed by NAD+ forming 2 NADH
Pyruvate produced by glycolysis enters the mitochondrion and is converted to acetyl CoA . During this step, NADH is produced from NAD+ + 2H(oxidation)
Most of the energy made available by the oxidative steps of the citric acidcycle is transferred as energy-rich electrons to NAD+, forming NADH. For eachacetyl group that enters the citric acid cycle, three molecules of NADH are produced.
D.In the absence of NAD+, glycolysis cannot function. As the primary purpose of glycolysis is the generation of ATP, NADH + H+, and pyruvate fromglucose.
E.NAD+ has less chemical energy than NADH.