The primary component of chlorophyll that absorbs light is magnesium. Chlorophyll is a green pigment found in plants, algae, and cyanobacteria, essential for the process of photosynthesis. It allows plants to capture light energy from the sun, which is then converted into chemical energy in the form of glucose. The structure of chlorophyll contains a porphyrin ring with a magnesium ion at its center, which plays a crucial role in the absorption of specific wavelengths of light, particularly in the blue and red spectrum, facilitating energy transformation in plants.