Aclownfish and a sea anemone what relationship is this ? the anemones have stinging tentacles that the clownfish are immune to, and the clownfish keeps the anemone parasite free.

This is a mutualistic symbiosis, in which both organisms benefit from the relationship.  The clownfish cleans the anemone, and feeds it to some extent (anemones are largely photosynthetic, thanks to a symbiotic relationship with photosynthetic algae, but will also eat fish, invertebrates, and food particles dropped by the clownfish), and the anemone gives the clownfish a safe place to call home.

tissue

explanation:

it is actually formed by geoup of cells which is tissue