Like "fossil fuel" or "respiratory system"?
The variety of organisms that occupy a given region including microscopic protists to large mammals. The region can be a political unit such as a country a geographic feature such as a mountain range or the entire world. The first level of bio diversity is genetic diversity. Next is taxonomic diversity. Also ecological diversity.
The waves move toward land. When waves crash into the land over a long time, they can break rock down into smaller pieces. These pieces are called sand. A shoreline is a place where the land and the water meet.
