What do the components of chemiosmosis do?

Chemiosmosis is a process by which ions, usually protons, are moved across a biological membrane, generating a proton gradient that powers the synthesis of ATP (adenine triphosphate) molecules. The main components of chemiosmosis are the electron chain transport, proton gradient, and ATP synthase. 

• Electron transport chain (ETC): The ETC is a series of protein complexes that lie embedded in the inner mitochondrial membrane in eukaryotes or the plasma membrane in prokaryotes. During cellular respiration or photosynthesis, protons move through the complexes in the electron chain transport, generating a proton gradient.
• Proton gradient: The proton gradient across the inner mitochondrial membrane is a key feature of chemiosmosis. It is generated by the transfer of protons (H+ ions) from the mitochondrial matrix to the intermembrane space as electrons move through the four enzyme complexes in the electronic transport chain. The proton gradient establishes a potential energy difference across the membrane. 
• ATP synthase: ATP synthase, an enzyme complex that is embedded in the inner mitochondrial membrane, utilizes the energy of the proton gradient to synthesize ATP molecules from ADP (adenosine phosphate) and inorganic (Pi).