Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Monera,taxonomic kingdom that comprises the prokaryotes (bacteriabacteria
[pl. of bacterium], microscopic unicellular prokaryotic organisms characterized by the lack of a membrane-bound nucleus and membrane-bound organelles. Once considered a part of the plant kingdom, bacteria were eventually placed in a separate kingdom, Monera.
..... Click the link for more information. and cyanobacteriacyanobacteria
or blue-green algae,
photosynthetic bacteria that contain chlorophyll. For many years they were classified in the plant kingdom along with algae, but discoveries made possible by the electron microscope and new biochemical techniques have shown them to be
..... Click the link for more information. ). Prokaryotes are single-celled organisms that lack a membrane-bound nucleus and usually lack membrane-bound organelles (mitochondria, chloroplasts; see cellcell,
in biology, the unit of structure and function of which all plants and animals are composed. The cell is the smallest unit in the living organism that is capable of integrating the essential life processes. There are many unicellular organisms, e.g.
..... Click the link for more information. , in biology). They have a small ring of DNA as their genetic material and reproduce asexually. A recently proposed system classifies these organisms in two major groupings called Eubacteria and ArchaebacteriaArchaebacteria
, diverse group of bacteria (prokaryotes), sometimes called the archaea and considered a major group unto themselves. Archaebacteria are contrasted with the Eubacteria, from which they differ biochemically in the arrangement of the bases in their ribosomal RNA and
..... Click the link for more information. , or archaea. Monera has been contrasted with the kingdoms of eukaryotic organisms (protists, fungi, plants, and animals; see eukaryoteeukaryote
, a cell or organism composed of cells that have a membrane-bound nucleus and organelles (mitochondria, chloroplasts; see cell, in biology) and genetic material organized in chromosomes in which the DNA is combined with histone proteins.
..... Click the link for more information. ).
A kingdom that includes the bacteria and blue-green algae in some classification schemes.