* Carbon dioxide (CO2): This is the source of carbon atoms for building sugars. It is taken in from the atmosphere through tiny pores called stomata on the leaves of plants.

* Water (H2O): Water is the source of hydrogen atoms and electrons needed for the process. It is absorbed by the roots of plants and transported to the leaves.

* Sunlight (energy): Sunlight provides the energy needed to drive the chemical reactions of photosynthesis. This energy is captured by a pigment called chlorophyll, which gives plants their green color.

So, the basic equation for photosynthesis is:

Carbon dioxide + Water + Sunlight → Glucose + Oxygen