The chemiosmotic hypothesis is an hpothesis is an important concept in our understanding of cellular metabolism in general because A. it explains how ATP is synthesized by a proton motive force B. it explains the reduction of o it explains the sequence of the electron transport chain molecules C. it explains how electron transport can fuel substrate-level phosphorylation it explains D. it explains the sequence of the electron transport chain molecules

The chemiosmotic hypothesis was given by Peter Mitchell in 1961. It states that ATP synthesis is coupled with proton motive force. This proton motive force is generated in the inner mitochondrial membrane when electrons are passed throw the electron carriers that are present in this membrane.

This proton motive force allow their transport of hydrogen ion in the intermembranal space against the concentration gradient and when these hydrogen molecule goes back in matrix through ATP synthase it generate ATP from ADP.

Therefore, the proton gradient is responsible for the formation of ATP was hypothesized in the chemiosmotic hypothesis so the right answer is A.