Chapter 22, Problem 13RE

Interpretation Introduction

Interpretation:

The electron transport chain that evolved first is to be determined.

Concept introduction:

Photosynthesis occurs in the presence of light, and water is converted to oxygen by oxidation and ${\text{NADP}}^{\text{+}}$ is reduced to $\text{NADPH}$.

${\text{NADP}}^{\text{+}}{\text{ + H}}_{\text{2}}\text{O }\to {\text{ NADPH + H}}^{\text{+}}\text{ + }\frac{1}{2}{\text{O}}_{\text{2}}$

The $\text{NADH}$ is oxidized to ${\text{NAD}}^{\text{+}}$, while oxygen is reduced to water. The reaction is given as :

$\text{NADH + }\frac{1}{2}{\text{O}}_{\text{2}}{\text{ + H}}^{\text{+}}\to {\text{ NAD}}^{\text{+}}{\text{ + H}}_{\text{2}}\text{O }$