Definition
noun, singular: archaebacterium
Unicellular microorganisms in the domain Archaea, which is genetically distinct from bacteria and eukaryotes, and often inhabiting extreme environmental conditions.
Supplement
Examples of archaebacteria include halophiles (microorganisms that may inhabit extremely salty environments), methanogens (microorganisms that produce methane), and thermophiles (microorganisms that can thrive extremely hot environments).
They evolved separately from eubacteria and eukaryotes. They are similar with eubacteria in being prokaryotes and lacking distinct cell nucleus. They differ in terms of ribosomal structure, the possession of introns and in membrane structure or composition. They are similar to eukaryotes in ways that archaea possess genes and several metabolic pathways that are more closely related to those of eukaryotes: notably the enzymes involved in transcription and translation.
Word origin: New Latin, from Greek arkhaion, neuter singular of arkhaios, ancient + bacteria.
Related forms: archaeobacteria.
Synonym: archaea.
Compare: eubacteria.
Dictionary > Archaebacteria
You will also like...
Human Biology – Food and Digestion
This tutorial recognizes the importance of food as a source of energy that will fuel many biological processes. A good d..
Types and Causes of Brain Damage
This tutorial describes the different types and causes of brain damage. Find out how genetics, physical injury, lack of ..
Still Freshwater & Plants
Plants in lentic habitats have features not found in terrestrial plants. They acquired these features as they adapt to t..
Meiosis and Alternation of Generations
Plants are characterized by having alternation of generations in their life cycles. This tutorial is a review of plant m..
Plant Water Regulation
Plants need to regulate water in order to stay upright and structurally stable. Find out the different evolutionary adap..
Growth and Development of a Human Baby
Upon fertilization, a zygote forms and develops into an embryo. This tutorial elaborates on the growth and development f..