Practice question

Phylum Tenericutes historically known as Mollicutes encompasses bacteria characterized by complete loss of peptidoglycan cell wall through reductive evolution due to parasitic lifestyle. Name derived from Latin tener meaning soft reflects wall-less pleomorphic nature. Cells bounded only by cholesterol-incorporated plasma membrane resist cell wall-targeting antibiotics like penicillin, exhibit filterability, and require isotonic host environments. Genome reduction to less than one megabase in some Mycoplasma exemplifies minimal free-living cells. Distinctive lack of rigid envelope separates them from Firmicutes, Actinobacteria, and Proteobacteria which produce walls.