Q. What is the path followed by the energy absorbed by plants to be used in photosynthesis?

The energy source of photosynthesis is the sun, the central and unique star of our planetary system. In photosynthesis the solar energy is transformed into chemical energy, the energy of the chemical bonds of the produced glucose molecules and of the released molecular oxygen. The energy of glucose is then stored as starch glucose polymer or it is used in the cellular respiration process and transferred to ATP molecules. ATP is consumed in metabolic processes that spend energy (for instance, blocked transport across membranes).