Some protists have cell walls, but not all of them do. Plant-like protists (AKA algae), and fungi-like protists (i.e., molds) both have cell walls, but animal-like protists (protozoa) do not.
Cell Walls in Plant-like Protists
Plant-like protists, or algae, usually have cell walls. These are similar to the cell walls of land plants in that they contain cellulose. Although most algae have cell walls some, such as the euglenids, don’t.
Cell Walls in Fungi-Like Protists
Fungi-like protists (AKA molds) also have cell walls containing cellulose. In this way, they are more similar to other protist species than true fungi, whose cell walls contain chitin.
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