The primary function of chlorophyll in plants is to capture light energy from the sun during the process of photosynthesis. This green pigment is primarily found in chloroplasts and absorbs light most efficiently in the blue and red wavelengths, reflecting green light, which is why plants appear green. Chlorophyll plays a crucial role in converting carbon dioxide and water into glucose and oxygen, using sunlight as the energy source. This process not only fuels the plant's growth but also contributes to the oxygen supply in the atmosphere, making chlorophyll essential for life on Earth.