Which kingdom is made up of single-celled prokaryotic organisms known for surviving in extreme conditions?

The kingdom that comprises single-celled prokaryotic organisms capable of thriving in extreme environments is Archaebacteria. These organisms are uniquely adapted to a variety of harsh conditions, such as high temperatures, high salinity, or extreme acidity, often found in environments like hot springs, salt lakes, and deep-sea hydrothermal vents.

The distinguishing feature of Archaebacteria is their unique biochemistry and genetics, which set them apart from other types of bacteria, particularly Eubacteria. While Eubacteria also includes prokaryotic organisms, they typically inhabit more moderate environments and lack the specific adaptations that enable Archaebacteria to survive extreme conditions.

In contrast, Protista and Fungi are kingdoms that consist of eukaryotic organisms, which are fundamentally different from prokaryotic Archaebacteria. Protista includes a variety of single-celled and multicellular organisms, but they do not encompass the extreme conditions that Archaebacteria are known for. Fungi, on the other hand, are primarily multicellular (with some unicellular exceptions, like yeast) and are not classified as prokaryotes, nor do they possess the resilience seen in Archaebacteria.

Thus, the definition and characteristics of