Protista, was a modification of an earlier term, Protoctista, which had been suggested a century earlier by a Scottish biologist named John Hogg, and was meant to describe any organisms that were neither plant nor animal.
Mixotrica paradoxa, one of those fibre-digesting components, is itself a composite of a protist, a single-celled eukaryote, and four types of bacteria.
That adds in the archaean, bacterial, fungal and protist cells which occupy the mouth, gut, skin, lungs and almost every other surface, nook and cranny of the human body.
Over the course of each day, the jellyfish migrate to follow the sunlight, so the protists can photosynthesize and make lots of energy-containing molecules.