Chemiosmosis is the diffusion of diffusion of hydrogen ions (protons) across a biological membrane via ATP synthetase (a transport protein) due to a proton gradient the forms on the other side of the membrane.
Chemiosmosis is one of the processes by which ATP is synthesized. In Eukaryotes, it take place in the mitochondria during cellular respiration and in the chloroplast during photosynthesis.
The process is called chemiosmosis because the chemical ions move from an area of higher concentration to an area of lower concentration through a semi-permeable membrane, just like water molecules.
