There is a lot of water in this reaction. Under normal conditions, water molecules are split apart and hydrogen ions are released to the environment. This is called hydrolysis. In order for glucose production to take place, there needs to be a way for these hydrogen ions to make their way back into the system without being lost or going outside of the cell membrane where they can be used again (hydrogen ion pumps).
The answer? Chloroplasts!
Chloroplasts are the cells in plant and algae that act as a mini-laboratory for making glucose. They have their own set of enzymes, including RuBisCO, which is one responsible for increasing water use efficiency by ixing hydrogen ions back into to the system where they can be used again. The chloroplast also has many thylakoid membranes within it — these function like batteries because they store chemical energy from sunlight via photosynthesis so when there isn’t enough light around or during night time hours (depending on how much solar radiation your region gets), this stored energy will power the reactions inside. This means less need for outside sources of fuel! This process makes sense given that plants