Algae are plants characterized by pigments that allow them to photosynthesize by capturing solar energy. They are not plants, since they do not have a conductive system, roots or flowers.
They are a very heterogeneous group of organisms, due to the pigments they can harbor. Regarding their size, it can vary from microscopic, such as xanthophytes, to tens of meters, as is the case of laminaria. The main groups that we can distinguish at a glance are: Chlorophytes (green algae), Phaeophytes (brown algae) or Rhodophytes (red algae).
As far as green algae are concerned, they form a division (what would be the phyllum in animals) that has in common the presence of chlorophyll A and B. In addition to multi-cellular species, there are also unicellular species. Most of them are freshwater algae, but in this guide we only show those that live in the sea.