Final answer:
The kingdom Archaebacteria is made up of bacteria that can survive in extreme environments. They are similar to other bacteria in size and structure but differ considerably in their molecular organization. Examples of these can be found in environments such as hot springs, extremely salty water, and even the digestive tracts of animals.
Step-by-step explanation:
Bacteria that survive in extreme environments belong to the Archaebacteria kingdom. Archaebacteria is a group of microorganisms that are similar to bacteria in size and simplicity of structure, but radically different in molecular organization. They are capable of surviving under extreme conditions like high acidity, temperature, salt concentration, etc. For example, Methanogens, a class of Archaebacteria, live in the guts of animals, including humans, and produce methane gas as a metabolic byproduct. Other members of the kingdom exist in hot springs, salty water, and other habitats which are extreme or harsh for most life forms.
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