What parts does algae have?

Before indicating which parts algae have, it should be noted that for them the most essential feature is the absence of such multicellular organs that others, higher plants have, namely, the root, stem and leaves. That is, the algae body is not divided into organs and does not have real tissues. This undivided body of algae is called thallus or thallus.
In this case, the thallus can be dressed in a shell or represent a colony consisting of at least four or more cells of both simple and branched filaments, as well as plates or any more complex formations that are similar in appearance to higher plants.