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

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Ramicristates

The Ramicristates are a diverse group of [[Sarcodina|amoeboid protists]] that are characterized by the presence of branching cristae within the mitochondria.  The vast majority of forms with lobose and filose pseudopods belong here.

The best-known member is ''[[Amoeba]]'' itself, found on decaying vegetation in freshwater streams and ponds.  A number of lobose pseudopods extend from the front of the creature, fusing around food to trap it in internal vacuoles and spreading out to pull the creature along the substrate.  The outer layer of cytoplasm, the ectoplasm, streams back from the pseudopods so acts like a tank-tread.  A single contractile vacuole expels water to maintain the osmotic balance.

A number of amoebae have protective shells.  These may be formed by collecting and cementing together particles of sand, as in ''[[Difflugia]]'', it may be secreted, as in ''[[Arcella]]'', or it may be formed out of individually manufactured plates, as in ''[[Euglypha]]''.

The true slime molds ([[Myxomycetes]]) also belong to this group.  These take the form of a multinucleate plasmodium, which grows to macroscopic size.  Eventually stalked sporangia develop and release haploid swarmers that go through an amoeboid and then a biflagellate stage.  New plasmodia form from the fusion of two swarmers.

Sporangia are also produced in the [[Dictyosteliida]] and [[Protostelida]], but these have a very different life cycle.  Individual amoebae under adverse conditions attract each other and pile up to form a slug.  The slug's cells are still capable of functioning individually - it will come apart if shaken - but it has a distinct front and back and undergoes differentiation to form a stalked sporangium after a short time.  Such creatures are called cellular slime molds, and also occur among the [[Acrasida]]; the [[Myxobacteria]] are also similar.