Molecular model of a light-harvesting three-coloured FCP trimer from diatom Thalassiosira pseudonana with the ligands shown in yellow-green. FCP stands for "Fucoxanthin-chlorophyll a/c protein". Diatoms have a unique light-harvesting system compared to green plants and other algae. They utilize FCP proteins along with chlorophyll a and chlorophyll c pigments to capture a wider range of wavelengths of light for photosynthesis.