What kingdom do unicellular organisms, that lack a nucleus, belongs to?
Unicellular organisms are also known as single-celled organisms, because they have only one cell. In comparison, multicellular organisms are those that contain a number of cells. Some common examples of unicellullar organisms are bacteria and archaea. The unicellular organisms that do not contain any nucleus are known as prokaryotes. All other organisms are classified as eukaryotes.
Prokaryotes or unicellular organisms, without a nucleus, are categorized in two different kingdoms: Eubacteria and Archaebacteria or simply, bacteria and archaea, respectively. Sometimes these two kingdoms are also clubbed together as Monera.
Unicellular organisms with a nucleus are part of the kingdom Protista. Eukaryotes form three different kingdoms, namely, Fungi, Plantae (consists of all the plants) and Animalia (consists of all the animals that we know about).
Bacteria are most widely known unicellular organisms that lack a nucleus.
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