Hello there,
Nekton are organisms that spend most of their time in the water column and can swim freely and faster than currents.
Plankton are organisms that live in the water column, but that either cannot swim or cannot swim faster than currents.
Benthos are the flora and fauna found on the bottom, or in the bottom sediments, of a sea or lake.
Thus, the major difference between these organisms is in their habitat.
Hope this helps :))
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