<span>The movement along the concentration gradients allows for the cell to maintain homeostasis. Keeping a cell in the proper conditions inside and out allows for it to function properly and carry out the duties that it is required to do as part of its bodily system.</span>
A planarian can regrow any missing body part. Truth be told, in the event that you take a planarian and excise it into a few little pieces, every last one of those body sections can recover into an entirely different worm.