What are he similarities and differences among a lake, wetland, and a river?

Essentially wetlands are the transition between dry land and water (streams, rivers,lakes, and coastlines), wetlands take many forms including the familiar marshes, swamps and bogs. Yet, not all wetlands are "wet" year round. These "drier end"wetlands also perform significant wetland functions. 
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the sugar phosphate backbone

Explanation:

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