Coral Reefs

Corals are in fact tiny animals, which most closely resemble anemones and jellyfish, and many have a very important symbiotic relationship with a microscopic plant or algae called zooxanthanellae which live inside their tissues. Reef building corals produce hard skeletons which are predominantly responsible for forming the reef structure.

Corals belong to the Kingdom Animalia and the Phylum Cnidaria. Cnidarians are a large group of relatively simple organisms, which can be characterised by a basic body structure, with two primary cell layers, an epidermis and an endodermis, separated in most species by a simple, supportive, jelly like matrix, the mesoglea and a rudimentary nervous system. A special feature of this group is the specially adapted cells known as cnidocytes that have a complex capsule or nematocyst that can release highly potent toxins and are used in the capture of prey or for defence.

Cnidarians are classified into four groups or Classes, possibly the best known of these groups are the jellyfish (Scyphozoa). Another of these classes is the Anthozoans under which the majority of coral species are classified. This class is a particularly large and diverse group of Cnidarians.