Green plants manufacture glucose through a process that requires light, known as photosynthesis.
This process takes place in the leaf chloroplasts.
Carbon dioxide and water molecules enter a sequence of chemical reactions within the chloroplasts.
The end products of these reactions are glucose and oxygen gas, which is released into the air. Glucose is used by the plant, with much of it being converted into other carbohydrates like starch and cellulose.
Glucose is a simple sugar with the molecular formula C6H12O6. It belongs to the carbohydrate class of macronutrients.