Corals | What is a coral, characteristics, types of corals, and coral reefs
“Corals” is a term referring to tiny animals that live in the sea and form the “coral reef” together with algae (zooxanthellae).
Hydra | What is a hydra, characteristics, classification, habitat, and diet
“Hydra” is a genus of cnidarians consisting of small animals with a cylindrical body, retractable tentacles, and an adhesive base or disc.