Order the steps through which atp synthesis occurs during the light-dependent reactions of photosynthesis in plants. the concentration of hydrogen ions in the thylakoid space increases. electrons move down the electron transport chain, releasing energy that pumps hydrogen ions into the thylakoid space. atp synthase uses the energy released as hydrogen ions move from regions of high concentration to regions of low concentration to make atp. hydrogen ions diffuse across the thylakoid membrane into the stroma through atp synthase. energy from the sun ejects electrons from chlorophyll and splits water molecules to yield hydrogen ions. ↓ ↓ ↓ ↓ reset next