Animal cells:
They are self sufficient, because of Nano-Chemical factories, so they can make their own stuff like cell membranes.
A cell can destroy itself through apoptosis in the event that it is irreparable.
Plant cells:
These were the first type of cells discovered by us.
Plants only actually use about 1/6 of the energy they get from photosynthesis, the rest is stored for animals that eat the plant.