ATP is synthesized in photosynthesis by which of the following means?
A) Light energy stored by chlorophyll of photosystem I is directly transferred to ATP synthase, which uses the energy to synthesize ATP.
B) Light energy absorbed by photosystems I and II generate energetic electrons that cause the cytochrome bf complex to pump protons across the thylakoid membrane; these protons drive ATP synthase to synthesize ATP.
C) Light energy absorbed by photosystems I and II generate energetic electrons that cause the cytochrome bf complex to pump protons across the inner chloroplast membrane; these protons drive ATP synthase to synthesize ATP.
D) Light energy is used to synthesize glucose, which is then metabolized to produce ATP.

Question

Quizplus · Accepted Answer

In photosynthesis, the energy from light is used to generate energetic electrons in both photosystems I and II. These electrons are transferred to the cytochrome bf complex, which uses the energy to pump protons across the thylakoid membrane. This gradient of protons drives ATP synthase to synthesize ATP. Therefore, option B is the correct choice. Option A is incorrect because photosystem I does not directly transfer energy to ATP synthase. Option C is incorrect because the protons are pumped across the thylakoid membrane, not the inner chloroplast membrane. Option D is incorrect because glucose is not directly converted to ATP in photosynthesis; glucose is used as a source of energy in cellular respiration to produce ATP.

ATP Is Synthesized in Photosynthesis by Which of the Following