Wikipedia 10K Redux by Reagle from Starling archive. Bugs abound!!!

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Eukaryotes are considerably more complicated than prokaryotes (KingdomMonera).

Each cell has at least one nucleus, a structure where the DNA is stored bound by a double membrane.  Generally there is more than one ChromoSome, and there are usually multiple copies of the same genes.  Nuclei divide through a process called NuclearMitosis, where microtubules pull apart the divided chromosomes and ensure each daughter has a full set.

Many eukaryotes also undergo a process of SexualReproduction.  This involves two phases: SynGamy, where two haploid (single gene set) cells fuse to form a diploid, and NuclearMeiosis, a process similar to mitosis where the chromosomes are divided to form haploids.  The role of haploid and diploid stages in the life cycle varies considerably.

There are a wide variety of intracellular organelles.  These include membrane bound structures, notably EndoplasmicReticulum and various-purposed vacuoles.  Nearly all eukaryotes have MitoChondria to burn food, and quite a few have ChloroPlasts for photosynthesis; these appear to actually be reduced endosymbiont bacteria.

Multicellular organization has arisen among the eukaryotes a number of times.  Of such forms, the KingdomAnimalia, KingdomPlantae, and KingdomFungi are typically listed separately as top-level taxa.  Other groups are left in the junk-basket category of KingdomProtista.  These include the following:

* TaxonEuglenozoa (euglenids, kinetoplastids)
* TaxonAlveolata (ciliates, dinoflagellates, apicomplexan sporozoa)
* TaxonChromista (stramenopiles: water molds, golden and brown algae, diatoms)
* FlagellateTaxa
* AmoeboidTaxa
* AlgalTaxa
* SlimeMolds