Which is correct about chemiosmotic synthesis of ATP as it occurs in the chloroplast (cp) and/or the mitochondria (mt) using an electron transport chain (ETC) ?

A) In the cp, protons get pumped bt the ETC into the inter-membrane space of the cp.

B) In the cp, ATP synthase will make ATP within the thylakoid spaces.

C) In both the cp and mt, electrons ultimately travel to ADP to make ATP.

D) In the mt, electrons that travel through the ETC eventually reach oxygen.

E) In the mt, electrons from the ETC are ultimately used to reduce electron carriers.

The correct answer will be option-D.

Explanation:

The chemiosmotic hypothesis explains the formation of the ATP molecules through the proton motive force generated by the flow of electrons through the electron transport chain. The electrons travel and lead to the movement of protons from thylakoid lumen to stroma in chloroplast while from the inter-membrane space to mitochondrial matrix in mitochondria.

The electron transport chain in mitochondria transports the electrons to the oxygen which gets reduced and adds protons to form the metabolic water.

Thus, option-D is the correct answer.