Question

question 7 of 10
what is the role of atp synthase in photosynthesis?
a. it produces atp by adding a phosphate group to nadp.
b. it uses the potential energy of flowing hydrogen ions to make atp.
c. it absorbs photons from the sun and gives energy to electrons.
d. it allows photons to be converted directly into glucose molecules.

Explanation:

ATP synthase is an enzyme complex. In photosynthesis, during the light - dependent reactions, a proton gradient (hydrogen ion gradient) is established across the thylakoid membrane. As hydrogen ions flow back down their concentration gradient (from the thylakoid lumen to the stroma) through ATP synthase, the enzyme uses the potential energy of this flow to catalyze the formation of ATP from ADP and inorganic phosphate ($ADP + Pi
ightarrow ATP$).

• Option A is incorrect because adding a phosphate group to NADP forms NADPH ($NADP^{+}+H^{+}+2e^{-}

ightarrow NADPH$), not ATP.

• Option C is incorrect because the absorption of photons and energy transfer to electrons is mainly the function of photosystems (photosystem I and photosystem II), not ATP synthase.
• Option D is incorrect because photons are not directly converted into glucose molecules. Glucose is synthesized in the Calvin cycle (light - independent reactions) using ATP and NADPH produced in the light - dependent reactions.

Answer:

B. It uses the potential energy of flowing hydrogen ions to make ATP.