Slide 6 of 17
Notes:
A coral contains a very thin outer layer of living coral polyps. Although
most corals contain hundreds or thousands of polyps, some contain
only one. The polyp is a hollow, cylindrical animal with a mouth that
is surrounded by tentacles armed with stinging cells for capturing
food. Underneath these coral polyps is the dead coral skeleton
composed of calcium carbonate. Each coral polyp excretes a calcareous
exo-skeleton that lives in a symbiotic relationship with zooxanthellae,
host algae located in the tissue of the polyp, that gives the coral its
green, blue, purple or brown color.
