Answer:
Coral reefs are shallow water tropical ecosystems. They are made up of hard material deposited by polyps which are tiny living organisms. The reefs protect the fragile shorelines from damage and erosion. They act as breeding grounds and shelter for many marine organisms. They are hotspots of marine bio-diversity and sources of potentially lifesaving medicines. They bring promise of medical cures that may come from the vast biodiversity of the ecosystems there.