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Eukaryotes are generally more advanced than prokaryotes. There are many unicellular
organisms which are eukaryotic, but all cells in multicellular organisms are
eukaryotic.
Characteristics:
- Nuclear membrane surrounding genetic material
- Numerous membrane-bound organelles
- Complex internal structure
- Appeared approximately one billion years ago
Examples:
- Paramecium
- Dinoflagellates
- sapiens
It is hypothesized that a primitive bacterium once surrounded its food after releasing
its digestive enzymes. The membrane folded inward and pinched off, creating the first
digestive membrane-bound organelle.
And now kids, it's storytime!
Once upon a time (about one billion years ago), the first eukaryotic cell came to be.
There was a group of primitive bacteria going about their business when along came
a big hungry phagocyte, who ate one of the bacterium.
Mr. Phagocyte: Yum.
Bacterium: Excuse me.
Mr. Phagocyte: What?
Bacterium: You know, why don't we join forces and I can help you and you can help me
and we can become a 'eukaryotic' cell? Whaddaya say?
Mr. Phagocyte: OK.
The little engulfed bacterium evolved and became the mitochondria in present-day cells.
Obviously, they all lived happily ever after. | 
