Question

Chemiosmotic theory of ATP synthesis in the chloroplasts and mitochondria is based on:

• A. Proton gradient
• B. Accumulation of K⁺ ions
• C. Accumulation of Na⁺ ions
• D. Membrane potential

Answer 1

The Correct Option is A

According to this theory, a proton (H⁺) gradient or proton motive force is established across the inner mitochondrial or thylakoid membrane, and ATP is synthesized as protons flow back through ATP synthase enzymes, driving the phosphorylation of ADP to ATP. This proton gradient is established through the electron transport chain during the process of oxidative phosphorylation in mitochondria and photophosphorylation in chloroplasts. 

So, the correct option is (A): Proton gradient