<human>:  What is the structure of chlorophyll?
<bot>: Chlorophyll is a molecule that absorbs light and converts it into energy. It is found in all photosynthetic organisms, including plants, algae, and cyanobacteria. Chlorophyll is made up of a magnesium ion, a central magnesium ion, and four porphyrin rings. The central magnesium ion is responsible for the absorption of light energy, while the porphyrin rings are responsible for the conversion of light energy into chemical energy.