It should continue to be restricted. If it is not restricted, there is a chance it will become extinct. This not only has bad consequences for us, it destroys the food web as a trophic level is effectively eliminated.
I would say ones that can be seen, it affects the physical era of life eg H20 one of its physical qualities is its clear... coloress
Is there a picture to go along with it? Or examples?
All eukaryotic cells have Membrane bound nucleus while Prokaryotes don't.