An observable characteristic of an organism that arises from environmental factors, or a combination of environmental and genetic (genotype) factors. Organisms with the same genotype can have very different phenotypes.
Class of organisms, including the eubacteria and archaea, that lack a true membrane-limited nucleus and other organelles. (Molecular Cell Biology/Harvey Lodish [et al.] - 4th)
Synonyms: prokarya, prokaryotes, prokaryotic organisms
A linear polymer of amino acids linked together in a specific sequence and usually containing more than 50 residues. Proteins form the key structural elements in cells and participate in nearly all cellular activities.