16. What's developed as a result of the electron transport chain?

The electron transport chain reaction occurs in the cristae of the mitochondria.

Electrochemical proton gradient

Explanation:

As electrons are passed from one protein complex to another in the mitochondria, the tapped energy is used to pump protons to the intermembrane space between the inner and outer mitochondrial membrane. This creates a proton motive forces whose potential is harnessed by the ATP synthase to phosphorylate ADP to ATP (the cell energy molecule).