There exist 2 major types of photosynthesis: oxygenic and anoxygenic photosynthesis. Oxygenic photosynthesis is most common in plants whereas anoxygenic photosynthesis is mostly common with bacteria lacking the nucleus.
In oxygenic photosynthesis, light is responsible for the transfer of electrons from water to carbon dioxide required for the production of carbohydrate. In order word, water is the oxidizing agent which loses its electron to produce oxygen whereas carbon dioxide is the reducing agent which accepts the electrons from water to produce carbohydrate.
The main differences between oxygenic and anoxygenic photosynthesis is that: In oxygenic photosynthesis, oxygen is being produced, but for anoxygenic photosynthesis there is no production of oxygen. in oxygenic photosynthesis, water is the electron donor,but for anoxygenic photosynthesis, water is not the electron donor.
This can be shown by the below listed equations
6CO2+12H2O+SUNLIGHT—>C6H12O6+6O2+6H2O representing oxygenic photosynthesis in which oxygen is being produced & CO2+2H2A+SUNLIGHT–>[CH2O]+2A+H2O Representing anoxygenic photosynthesis with no production of oxygen in which A will represent any variable.
Photosynthesis in green plants actually takes place in the chloroplast which will be explained in the next chapter. Both the light and the dark stage of the photosynthetic reaction takes place at the level of the chloroplast