Why the drastic difference between plant and animal cell lengths?
It is due to the basic structural difference between animal and plant cell. Plant cells have a much more rigid cell wall, surrounding the cell and thus limiting growth once the cell has reached maturity. animal cells have a more “flexible” cell membrane and will still double in size at time of replication and prior to division (there needs to be enough material for 2 cells). For growing plant cells, like for roots, the main growth direction is downward (this is directed by different hormones present in the plant which are able to tell which side is “up” or “down”), the cells have grown to a certain size and now the wall is set, the only way to grow is down, so the cell will rearrange its internal structure so that the cells grows more vertically, which will make the cell appear much larger than orginially (or matured).
