Photosynthesis
Light absorption:
The green pigment chlorophyll, found in tiny cell parts called chloroplasts, absorbs sunlight. This happens mostly in the leaves.
Exciting electrons:
The light energy makes electrons in chlorophyll get excited — meaning they gain energy and start moving faster.
Energy transfer through reactions:
These energized electrons travel through a set of chemical steps called the electron transport chain. As they move, their energy is used to make two special energy-carrying molecules — ATP (adenosine triphosphate) and NADPH.
Glucose production:
In the second stage, called the Calvin cycle, the energy stored in ATP and NADPH is used to combine carbon dioxide (CO₂) from the air with hydrogen from water (H₂O) to make glucose (C₆H₁₂O₆).
Result — chemical energy:
The glucose made is a form of chemical energy. Plants use it to grow, make food, and give energy to other living things that eat them.
So in short:
Sunlight → absorbed by chlorophyll → converted to ATP and NADPH → used to make glucose → stored as chemical energy.