ICANT writes:
A sponge is a unicellular animal that has no muscles, nerves or internal organs.
Unicellular? Perhaps you should have kept reading the wikipedia page on sponges, specifically under the heading of anatomy and morphology.
A sponge is comprised of a number of different cells that all do very different things. A sponge does not have any muscles or internal organs because these other cells perform those functions. Yet, all of these cells work in conjunction with one another to produce a rather prodigious creature.
And the Ignorant shall fall to the Squirrels - Chip 2:54
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