Further to the questions spawned by my Central American vacation; I had a look at a jellyfish, this got me thinking. I know that jellyfish are invertebrates and are completely see-through, but how do they know what to do to survive? So, today’s question is: do jellyfish have brains?
A:
Jellyfish do not have a brain or a central nervous system, yet they function on an elementary nerve net. They have limited control of movement and generally are pushed along with the ocean currents, however can propel themselves through contractions of their body. Jellyfish eat by collecting small fish, plankton and microbial organisms as they swim; they use their tentacles to sweep food into their mouths.
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