Why can't a cell from a mullticellular organism survive on its own?

I think because it's not a differentiated cell

I hope this information helps you :)! 

Linnaeus divided nature into three kingdoms: animals, vegetable (or plant),  and minerals. The animal and plant kingdoms were further divided into  smaller, more inclusive categories based on physical characteristics.  As time passed, and knowledge increased, other scientists added to  Linnaeus’ original system.

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