Corals
are the major building blocks in reef formation. their importance
is dependant on the coral-zooxanthellae relantionshipp. The zooxanthellae
help the corals produce limestone in an efficient manner. It is not
necessary for corals to be the dominant benthic organisms. Incorporated
in the reef structure are larger molluscs together with calcareous plants
cemented by sand-sized sediments. The most common reef building coral
in the Great Barrier Reef is those that belong to the Acropora genus.
Acropora are a type of branching coral.