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Since NAD+ and NADP+ are essentially equivalent in their tendency to attract ele

ID: 963617 • Letter: S

Question

Since NAD+ and NADP+ are essentially equivalent in their tendency to attract electrons, discuss how the two concentration ratios might be maintained inside cells at greatly differing values.

Check all that apply.

1.Because NAD+-dependent enzymes usually act to dehydrogenate (oxidize) substrates, an [NAD+]/[NADH] ratio greater than unity tends to drive reactions in that direction.

2.[NADP+]/[NADPH] ratio less than unity provide concentrations that tend to drive these reactions in the direction of substrate oxidation.

3. Because NADH-dependent enzymes usually act to hydrogenate (oxidize) substrates, an [NAD+]/[NADH] ratio greater than unity tends to drive reactions in that direction.

4. Because NAD+-dependent enzymes usually act to hydrogenate (reduce) substrates, an [NAD+]/[NADH] ratio greater than unity tends to drive reactions in that direction.

5. [NADP+]/[NADPH] ratio less than unity provide concentrations that tend to drive these reactions in the direction of substrate reduction.

6. [NADP+]/[NADPH] ratio less than unity provide concentrations that tend to drive these reactions in the direction of enzyme oxidation.

Explanation / Answer

The ratio of NAD+ and NADH are essential in the cell for proper functioning. The concentrations are maintained inside the cells at different values,

1. Because NAD++-dependent enzymes usually act to dehydrogenate (oxidize) substrates, an [NAD+]/[NADH] ratio greater than unity tends to drive reactions in that direction.

5. [NADP+]/[NADPH] ratio less than unity provide concentrations that tend to drive these reactions in the direction of substrate reduction.