All living organisms are classified into one of three domains: bacteria, archaea, and eukarya. compare and contrast the domains bacteria and archaea. how are they alike? how are they different? a) they are both composed of prokaryotic organisms. bacteria are parasites and archaea are free-living. b) both domains contain parasitic organisms composed of one cell. the archaea are the disease-causing parasites. c) they are both composed of prokaryotic organisms. the archaea live in very extreme environments, like hot springs, but the bacteria do not. d) both are unicellular, prokaryotes. the archaea live as parasites while the bacteria live in extreme environments, like the salt flats and hot springs.

The most appropriates answer would be C) They are both composed of prokaryotic organisms. The Archaea live in very extreme environments, like hot springs, but the Bacteria do not.

Archaea are prokaryotic unicellular organisms that is, they lack well defined nucleus. However, they have distinct chemical or molecular characteristics which differ them from the bacteria.

These organisms were originally discovered in extreme conditions such as hydrothermal vents. They can survive in diverse range of high acidic, saline, and anaerobic environment. They are also termed as extremophiles.

On other hand, bacteria are also prokaryotic unicellular organisms. They can inhabit in any area including air, water, soil, decaying organism et cetera however, they are usually not found in such extreme conditions in which archaea can survive.

For example, Pyrolobus fumarii can survive even at 113 °C  temperature.