Crossword clues for protist
The Collaborative International Dictionary
Protist \Pro"tist\, n. (Zo["o]l.) One of the Protista.
Douglas Harper's Etymology Dictionary
1869, from Modern Latin Protista (German Protisten, Haeckel, 1868), from Greek neuter plural of protistos "the very first," superlative of protos "first" (see proto-).
Wiktionary
n. 1 (context microbiology English) Any of the eukaryote unicellular organisms including protozoans, slime molds and some algae; historically grouped into the kingdom ''Protoctista''. 2 # single celled eukaryotes + prokaryotes + sponges (to 1959) 3 # single-celled eukaryotes + prokaryotes (1959 - 1969) 4 # single celled eukaryotes (1969 - )
WordNet
n. free-living or colonial organisms with diverse nutritional and reproductive modes [syn: protistan]
Wikipedia
Protists are the members of an informal grouping of diverse eukaryotic organisms that are not animals, plants or fungi. They do not form a natural group, or clade, but are often grouped together for convenience, like algae or invertebrates. In some systems of biological classification, such as the popular 5-kingdom scheme proposed by Robert Whittaker in 1969, the protists make up a kingdom called Protista, composed of "organisms which are unicellular or unicellular-colonial and which form no tissues."
Besides their relatively simple levels of organization, protists do not necessarily have much in common. When used, the term “protists” is now considered to mean similar-appearing but diverse phyla that are not related through an exclusive common ancestor, and that have different life cycles, trophic levels, modes of locomotion, and cellular structures. In the classification system of Lynn Margulis, the term protist is reserved for microscopic organisms, while the more inclusive term Protoctista is applied to a biological kingdom which includes certain large multicellular eukaryotes, such as kelp, red algae and slime molds. Other workers use the term protist more broadly, to encompass both microbial eukaryotes and macroscopic organisms that do not fit into the other traditional kingdoms.
In cladistic systems, there are no equivalents to the taxa Protista or Protoctista, both terms referring to a paraphyletic group which spans the entire eukaryotic tree of life. In cladistic classification, the contents of Protista are distributed among various supergroups ( SAR, Archaeplastida, Excavata, Opisthokonta, etc.) and "Protista", ''Protoctista'' and " Protozoa" are considered obsolete. However, there still remains some ambiguity about the position in the cladistic tree of some taxa - such as most excavata ( metamonads, jakobids, Malawimonas and Collodictyon) and the term "protist" continues to be used informally as a catch-all term for Eukaryotic microorganisms - for example "protist pathogen" is used to denote any disease causing microbe which is not bacteria, virus, viroid or metazoa.
Usage examples of "protist".
Compared with the bacteria that had gone before, these new protists were wonders of design and sophistication.
Mammals, marsupials, monotremes, birds, reptiles, worms, insects, arachnids, crustaceans, planaria, nematodes, protists, fungi, even a horticultural center.
Earth, he sought to understand the evolution of the bacteria and protists, the fungi, plants, animals and all the alien kingdoms of life.
Old Earth and a million other worlds much like Earth, he sought to understand the evolution of the bacteria and protists, the fungi, plants, animals and all the alien kingdoms of life.
Both the oceans and the land harbor large populations of protist and multicellular autotrophs.
There are many different varieties of pathogen: viruses, bacteria, fungi, protists (formerly known as protozoa), and metazoans such as nematodes.