There are organelles in the plant cell that the animal cell does not have. Plant cells have rigid cell walls and animal cells have flexible cell membrane. Plant cells contains chloroplasts, which is something animal cells don't have. Also, large, liquid filled vacuoles can only be found in plant cells, and they can occupy up to 90% of a cell's volume. By looking at the cell and see if they have any of these characteristics determines if it is plant cell or animal cell.
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