Unicellular organisms excrete waste by a contractile vacuole. A vacuole is membrane-enveloped organelle in a cell that is found in lots of microorganism. It expands, filling with water then contracts, removing all of its contents to the exterior of the cell.
The correct answer is: [B]: "beneficial" .
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{<u>Note:</u> A symbiotic relationship known as "mutualism" — in which both organisms benefit.}.
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RNA, in one form or another, touches nearly everything in a cell. RNA carries out a broad range of functions, from translating genetic information into the molecular machines and structures of the cell to regulating the activity of genes during development, cellular differentiation, and changing environments.
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Decent from a common ancestor; natural selection.
