Suppose the interior of the thylakoids of isolated chloroplasts were made acidic and then transferred in the dark to a pH 8 solution. What would most likely happen?
A) The isolated chloroplasts would make ATP.
B) The Calvin cycle would be activated.
C) Cyclic photophosphorylation would occur.
D) The isolated chloroplasts would generate oxygen gas.
E) The isolated chloroplasts would reduce NADP+ to NADPH.

Question

Quizplus · Accepted Answer

The acidification of the thylakoid interior creates a proton gradient across the thylakoid membrane. When these chloroplasts are placed in a basic solution (pH 8), the proton gradient drives ATP synthesis through chemiosmosis, even in the dark, without the need for light-driven electron transport. This process is similar to the light-dependent reactions of photosynthesis, where the energy from the proton gradient is used by ATP synthase to generate ATP.

Suppose the Interior of the Thylakoids of Isolated Chloroplasts Were