Monera

Monera taxonomic kingdom that comprises the prokaryotes ( bacteria and cyanobacteria ). Prokaryotes are single-celled organisms that lack a membrane-bound nucleus and usually lack membrane-bound organelles (mitochondria, chloroplasts; see cell , 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 Archaebacteria , or archaea. Monera has been contrasted with the kingdoms of eukaryotic organisms (protists, fungi, plants, and animals; see eukaryote ).

Monera One of the five kingdoms of life in the classification originally proposed by R. H. Whitaker (1959, 1969), comprising the prokaryotic Cyanophyta (blue-green algae) and bacteria (Schizomycophyta). The bacteria were the first forms of life on Earth, dating from at least 3300 million years ago, while the first cyanophytes appeared about 2600 million years ago.

Monera In some taxonomic schemes, one of the 5 kingdoms of life, comprising the prokaryotic Cyanophyta’ (cyanobacteria) and ‘Schizomycophyta’ (other bacteria). Prokaryotes are currently placed into more fundamental categories (see ARCHAEA and EUBACTERIA). Bacteria are believed to have been the earliest forms of life on Earth, dating from at least 3300 Ma ago, while the first cyanobacteria appeared about 2600 Ma ago.