Question

Protons $\left(H^{+}\right)$ accumulate in the thylakoid space during electron transport between photosystems-I and II. The excess of protons in the thylakoid space

• A. enters the photorespiration pathway
• B. converts NADP to NADPH and generates ATP in the process
• C. is small enough to diffuse back out through the lipid bilayer
• D. moves from the thylakoid space by the stroma through an ATP synthase complex channel th generates ATP

Answer 1

The correct option is D moves from the thylakoid space by the stroma through an ATP synthase complex channel th generates ATP

Light induces electron transfer through photosystems II and I and the cytochrome bf6 complex. At various stages in this process, protons are released into the thylakoid lumen or taken up from the stroma, generating a proton gradient. The proton-motive force generated by the light reactions is converted into ATP by the ATP synthase of chloroplasts.

So, the correct option is 'moves from the thylakoid space by the stroma through an ATP synthase complex channel that generates ATP'.