(N/A) The mechanism of photosynthesis involves the following three main steps:
$1$. Absorption of light energy by chlorophyll: The green pigment chlorophyll present in the chloroplasts of plant cells absorbs solar energy.
$2$. Conversion of light energy into chemical energy: The absorbed light energy is used to split water molecules $(H_2O)$ into hydrogen and oxygen. This process is known as photolysis. Chemical energy is stored in the form of $ATP$ and $NADPH$.
$3$. Reduction of $CO_2$ into carbohydrates: The chemical energy generated is used to reduce carbon dioxide $(CO_2)$ into glucose $(C_6H_{12}O_6)$,which serves as the primary food source for the plant.