- Lipid bilayer (highlights: phosphoglycerides such as phosphatidylethanolamine or cephalin, phosphatidylcholine or lecithin, phosphatidylinositol and phosphatidylserine; sphingolipids formed by ceramide and fatty acids, and cholesterol)
- Proteins: integral, peripheral and membrane fixed to lipids.
- Glucids: covalently bound to proteins or lipids; they can be poly or oligosaccharides. They form the glycocalix on the outside of the membrane and its function is to support the membrane and cell recognition.
Answer: The biological definition of Archaea is any of the unicellular microorganisms that is genetically distinct from bacteria and eukaryotes, and often inhabiting extreme environmental conditions.
