In an Enzymatic Reaction Involving NADH or NADPH, Reduction of a Substrate

question 28

Multiple Choice

In an enzymatic reaction involving NADH or NADPH, reduction of a substrate accompanies the oxidation of these carrier molecules to NAD⁺ or NADP⁺, respectively. What else typically happens in such a reaction?

• A) A molecule of water is released to the solution upon completion of the reaction.
• B) A proton is released during the oxidation of the carriers.
• C) A proton is taken up by the substrate that is being reduced.
• D) A proton is taken up by the carrier molecule that is being oxidized.
• E) A phosphate group is transferred to the substrate.

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Definitions:

S-T Segment

The part of an ECG between the S and T waves, representing the period when the ventricles of the heart are depolarized, which should be flat if the heart muscle is receiving adequate oxygen.

P Wave

The deflection in an electrocardiogram (ECG) that represents atrial depolarization,preceding the contraction of the atria.

Q-T Interval

A measurement on an electrocardiogram (ECG) that represents the time between the start of the Q wave and the end of the T wave, indicative of the duration of ventricular depolarization and repolarization.

Ventricular Contraction

The phase of the cardiac cycle in which the ventricles contract, pumping blood out of the heart into the systemic and pulmonary circulations.