Final answer:
Archaea and bacteria are differentiated by their cell wall composition, membrane lipids, and ribosomal proteins. Archaea often inhabit extreme environments and follow unique metabolic pathways like methanogenesis, and are not known to cause diseases in humans.
Step-by-step explanation:
Differences Between Bacteria and Archaea
Even though both groups are unicellular, prokaryotic organisms and have single circular chromosomes, these significant biochemical and genetic differences underpin the separation of archaea and bacteria into their respective domains. Moreover, many archaea are extremophiles, thriving in harsh conditions where most life forms cannot survive. Archaea also have unique metabolic pathways such as methanogenesis, and they are not known to cause disease in humans, whereas some bacteria can be pathogenic.