Question

NADP is reduced to NADPH in

• A. HMP
• B. Calvin Cycle
• C. glycolysis
• D. EMP.

Answer 1

The Correct Option is A

To solve the question regarding where NADP is reduced to NADPH, let's explore each of the given options and understand where this process occurs:

1. HMP (Hexose Monophosphate Pathway):

   The HMP shunt, also known as the pentose phosphate pathway (PPP), is a metabolic pathway parallel to glycolysis. A significant role of this pathway is the generation of NADPH. In this cycle, glucose-6-phosphate is oxidized, and NADP⁺ is reduced to NADPH. The production of NADPH is crucial for biosynthetic reactions and combating oxidative stress in cells.

2. Calvin Cycle:

   This cycle, also called the Calvin-Benson cycle, is a part of photosynthesis in chloroplasts where ATP and NADPH generated from the light reactions are used for synthesis of glucose from carbon dioxide. However, the reduction of NADP⁺ to NADPH does not occur here; it happens during the light-dependent reactions of photosynthesis instead.

3. Glycolysis:

   Glycolysis is the process of breaking down glucose into pyruvate, earning ATP and NADH in the process, not NADPH. NADPH generation is not a characteristic of glycolysis.

4. EMP (Embden-Meyerhof-Parnas pathway):

   EMP is actually another name for the glycolytic pathway. As stated previously, this pathway generates NADH, not NADPH.

Based on the above explanations, the correct answer is the HMP shunt, where NADP⁺ is reduced to NADPH. This makes the option HMP the correct choice.