Coral Reefs
A coral reef is a ridge of living coral, coral skeletons, and calcium carbonate deposits from organisms such as calcareous algae, mollusks, and protozoans. The resulting structure provides a critical habitat for a wide variety of fish and marine invertebrates. Coral reefs also protect shores against erosion by causing large waves to break and lose some of their force before reaching land. More than 90% of the estimated 109,800 sq mi (284,300 sq km) of reefs in the world are in what region? More… Discuss
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