Which of the following events are associated with chemiosmosis in chloroplasts?
A) The pH of the stroma increases and ATP is synthesised.
B) The pH of the thylakoid space increases and ATP is synthesised.
C) The pH of the cytoplasm outside the chloroplast decreases and ATP is synthesised.
D) The pH of the stroma decreases and ATP is hydrolysed.

Question

Quizplus · Accepted Answer

Chemiosmosis occurs in chloroplasts during photosynthesis and involves the pumping of protons (H+) from the stroma to the thylakoid space. This creates a proton gradient, which is used to drive ATP synthesis by ATP synthase in the thylakoid membrane. As protons flow back across the membrane through ATP synthase, the pH in the thylakoid space increases, resulting in the synthesis of ATP. The pH of the stroma may change as a result of this process, but it is not directly involved in chemiosmosis. The cytoplasm outside the chloroplast is not affected by this process. ATP is not hydrolyzed during chemiosmosis, but rather synthesized.

Which of the Following Events Are Associated with Chemiosmosis in Chloroplasts