Anatomy & Physiology

Most scleractinian corals are found in colonies composed of a few to thousands of polyps. Colonies do not have symmetry but theindividual polyps present a radial symmetry around the oral disc. Polyps are the single organisms that have their own digestive system and could survive on their own but usually are found as colonies. Despite the polyps are individual organisms they share tissue and the skeleton with the other polyps of the colony, so they share fluids and nutrients among them (Ruppert et al 2004). Most corals, like Favia corals, have a symbiotic relationship with a micro algae called zooxanthellae.The zooxanthellae is a dinoflagellate that finds protection inside the tissues of the coral and does photosynthesis so it repays its protection with the products of photosynthesis produced in excess. Sometimes this relationship provides all the energy that coral needs to survive but they can also capture food from the water column with their tentacles and digest it on blind guts that each polyp has (Ruppert et al 2004).