What are Zooxanthellae?

Answer by  quisqualis (1756)

They are symbiotic dinoflagellate potozoans in the genus Symbiodinium, that live inside of other protozoans and invertebrates. Because Zooxanthellae are photosynthetic, they make their own food using sunlight. Corals, giant clams and some jellyfish receive energy from their Zooxanthellae, and die if they lose them.

Answer by  SashaDarkCloud (5764)

They are single celled plants that live inside the tissue of animals. They are usually found floating around in the sea, and the best example of this is plankton, which looks nothing like the character from Spongebob.