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  • Oceans and Seas
    Oceans and Seas
    A great expanse of continuous bodies of salt water which together cover more than 70 percent of the earth's surface. Seas may be partially or entirely enclosed by land, and ar...<br/>Year introduced: 1987
    MeSH
  • Lakes
    Lakes
    Inland bodies of still or slowly moving FRESH WATER or salt water, larger than a pond, and supplied by RIVERS and streams.<br/>Year introduced: 2012
    MeSH

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