What Substance Serves as the Electron Donor for Most Reductive

question 1

Multiple Choice

What substance serves as the electron donor for most reductive biosynthetic pathways?

• A) NADPH
• B) NADH
• C) FADH₂
• D) FMNH₂
• E) None of the answers is correct.

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Definitions:

Plasma Membrane

The semipermeable membrane surrounding the cytoplasm of a cell, regulating the passage of molecules in and out of the cell.

Sodium-Potassium Pump

A vital cell membrane protein that pumps sodium ions out of and potassium ions into cells, essential for maintaining cellular electrochemical gradients.

ATP

Adenosine triphosphate, a molecule that carries energy within cells, serving as a primary energy currency for cellular processes.

Exocytosis

A process by which a cell transports secretory products through the cytoplasm to the plasma membrane and then into the extracellular space.