Question

Explain how organisms are placed into the three major cell lineages or domains. View Available Hint(s) Explain how organisms are placed into the three major cell lineages or domains. analysis of ribosomal RNA analysis of DNA metabolic characteristics physical characteristics?

Answer 1

Answer:

The three main domains into which the organisms are classified are archaea, bacteria and eukarya.

Archaea : The archaea is more closely related to eukaryotes. Although they have bacteria like metabolism and  have 70'S chromosomes but shows presence of introns and shows similar molecular mechanism like replication, transcription and translation similar to eukaryotes. These are found in the extreme conditions as well.

Bacteria: The bacteria have circular DNA with 70'S ribosomes. The cell membrane has ester linkage and no nucleosome formation occur in bacteria. The transcription and translation are coupled together with no further modification.

Eukarya: The eukaryotes have linear DNA with 80'S ribosomes. The cell membrane has ether linkage and proper nucleosome fprmation occurs in eukarya. The transcription and translation occurs separately in the distinct compartments and further modification occurs.