Question

All of the following are characteristics of noncyclic photophosphorylation except

A) electrons return to the photosystem that generated them
B) electrons are obtained from molecules such as water
C) Both ATP and NADPH are generated
D) it occurs in all plant and algae
E) it requires photosystem I and II

Answer 1

In noncyclic photophosphorylation, electrons do not return to the photosystem that generated them. This process involves both photosystem I and II and occurs in plants and algae, producing ATP and NADPH.

Step-by-step explanation:

The student's question pertains to a characteristic that is not associated with noncyclic photophosphorylation. The correct answer is that electrons do not return to the photosystem that generated them in noncyclic photophosphorylation. Instead, electrons from water replace those lost in photosystem II, and the spent electrons from photosystem II replace electrons in photosystem I, creating a forward-flowing electron transport chain. This process is different from cyclic photophosphorylation, where the same electron is reused. Noncyclic photophosphorylation requires both photosystem I and II and occurs in most plants and algae, leading to the production of both ATP and NADPH, which are essential for the Calvin cycle.