During the process of photosynthesis, plants utilize sunlight and convert it into useful products, according to the following well-balanced chemical equation:
6CO_2 + 6H_2O + sunlight -> C_6H_12O_6 + 6O_2
In this reaction, glucose (a common sugar) is produced. These glucose molecules are used by the plant in a number of ways. The most common use is the production of energy (in the form of ATP molecules) through the process of cellular respiration. This process can be summarized by the following equation:
C_6H_12O_6 + 6O_2 -> 6CO_2 + 6H_2O + ATP
During the daytime hours, when photosynthesis is taking place, plants produce more glucose than they can consume. This extra glucose is stored in the plant in the form of starch. Cell walls are made up of starch and that is where much of the extra glucose is used. Sugars are also stored in other parts of the plant. Apart from starch, sugars can be also be stored as fats and oils.
Glucose can also be converted to sucrose and stored in fruits, stem, roots, seeds, etc. Glucose can also be used in the formation of amino acids, which are then used for protein synthesis in the plants.
Hope this helps.
