algae is usually green in color
yellow_green_algae is not algae. green_algae is alga. brown_algae is algae. green_algae is not algae. yellow_green_algae is not alga. green_algae is algae. green_algae is marine_organism. yellow_green_algae is algae. yellow_green_algae is alga. cyanobacteria is blue_green_algae.