water depth measured to the ocean floor from the water surface;
the oceanic equivalent of topography.
calcification
the process by which corals extract calcium from seawater and
create calcium carbonate.
cnidaria
an animal phylum characterized by stinging cells called
nematocysts, that contains the stony (hard) corals, anemones,
sea fans, sea pens, hydras, and jellyfish.
coral
a group of marine animals belonging to the phylum cnidaria,
that exist as small sea anemone-like polyps, typically in
colonies of many identical individuals; or the skeletal remains
of coral polyps.
coral bleaching
the loss of color in corals due to stress-induced expulsion of
symbiotic zooxanthellae algae.
coral polyp
a small individual coral animal with a tube-shaped body and a
mouth surrounded by tentacles.
coral reef
aragonite (calcium carbonate) structure produced by corals and
found in shallow, tropical marine waters.
molecular diffusion
the process by which carbon dioxide moves freely between air
and sea. The exchange occurs in a film of water at the surface.
Carbon dioxide travels wherever concentrations are lowest. If
levels in the atmosphere are high, the gas goes into the ocean.
If they are higher in the sea, as they have been for much of
the past, the gas leaves the water and enters the air.
mutualism
symbiotic relationship in which both species benefit.
photosynthesis
the process by which plants make sugar from sunlight, water,
and carbon dioxide.
respiration
process inside living cells in which sugars and oxygen are
turned into carbon dioxide, water and energy.
salinity
the concentration of salts dissolved in water.
symbiosis
the close association of two different organisms, in which one
or both benefit from the relationship.
watershed
area of land where all the water that is under it or drains off
of it goes into the same place.
zooxanthellae
any of various yellow-green algae that live symbiotically
within the cells of other organisms, such as reef-building
coral polyps.