EVERYDAY SCIENCE

Detailed explanation-1: -The two prokaryote domains, Bacteria and Archaea, split from each other early in the evolution of life. Bacteria are very diverse, ranging from disease-causing pathogens to beneficial photosynthesizers and symbionts. Archaea are also diverse, but none are pathogenic and many live in extreme environments.

Detailed explanation-2: -Bacteria encompass two domains: eubacteria and archaea. Eubacteria and archaea have very different cell walls. They are also distinguished by their DNA-the DNA of archaea has histone proteins while that of eubacteria does not.

Detailed explanation-3: -The two-domain system is a biological classification by which all organisms in the tree of life are classified into two big domains, Bacteria and Archaea.

Detailed explanation-4: -Prokaryotes are divided into two domains because studies on the organisms determined that there are enough differences to place them into their own groups.

Detailed explanation-5: -Prokaryotes include Bacteria and Archaea while the photosynthetic prokaryotes include cyanobacteria carrying out photosynthesis.