The NADPH generated by the pentose phosphate pathway primarily serves as a

a. reductant in biosynthetic pathways.
b. regenerates ribulose 1,5‑bisphosphate for the Calvin cycle.
c. links the oxidation of sugars to the mitochondrial electron transport chain.
d. serves as a replacement for NADPH generated by photosynthesis in carbon fixation.

Option-A

Explanation:

Pentose phosphate pathway is the alternative pathway taking place in both eukaryotes and prokaryotes parallel to the glycolysis.

The pentose phosphate pathway forms the electron carriers called NADPH and the ribose-5 phosphate.

The NADPH is formed in large amounts through this pathway which contains a very high amount of energy. NADPH can donate its hydride ions, therefore, it can be involved in the reaction where it can donate energy in the form of hydrogen and electron.

The NADPH is therefore involved in the formation of reducing biosynthetic pathways like fatty acid synthesis, cholesterol synthesis, and bile acid synthesis.

Thus, Option-A is the correct answer.

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.