Which of the following about electron transport chain is true:
a. protons are pumped out of the mitochondria by the complexes of the electron transport chain
b. the proton gradient established during electron transport is a form of p otential energy
c. the electron transport chain can be found in the mitochondria of aerobic bacteria and other cells.
d. the movement of protons down a concentration gradient is an endergonic process
e. ATP synthesis associated with the electron transport chain is an example of substrate level phosphorylation
The correct answer is provided