Question

Why does euglina doesn't belong to kingdom animalia whereas algae does

Answer 1

Euglena do photosynthesis using the same basic process that plants use. They also move around and eat, as do animals. But you are right that they are not classified as either of these. That is because they are unicellular. “Uni” means one (a unicycle has one wheel). In order to be classified as a plant or animal, an organism has to be multicellular, or made of more than one cell. Since it is a unicellular organism with some plant and animal characteristics, it is called a protist. Plant cells have walls. There’s no cell wall around a Euglena’s cell membrane, so it is a protozoan. It used to belong to the kingdom Protista.