Supplement. Archaea or archaebacteria 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 (in some species) and in membrane structure or composition.rchaea or archaebacteria evolved separately from eubacteria and eukaryotes. They are similar with eubacteria in being prokaryotes and lacking distinct cell nucleus.
Definition of COGENCY. : the quality or state of being cogent.See cogency defined for kids. ADVERTISEMENT.efinition of COGENCY. : the quality or state of being cogent.
Also called (for senses 1, 2): divergency or divergement. (dÉªËvÉr dÊÉns, daÉª-) n. 1. an act or instance of diverging. 2. a divergent state or quality. 3. the degree or point of diverging. 4. a difference of structure in related organisms caused by different environmental pressures. 5. the net flow of air from a given region.