Question

the sequencing of rrna allowed scientists a clear understanding that certain nucleic acid sequences are unique to archaea and eukaryotes. that all dna is relatively the same across domains. that half of the sequences of archaea were previously unknown. of the unambiguous relationships among different prokaryotic species. that archaea are more similar to bacteria than to eukaryotes.

Explanation:

The sequencing of rRNA (ribosomal RNA) has been crucial in understanding the evolutionary relationships and unique features of different organisms. Archaeal and eukaryotic nucleic - acid sequences have distinct characteristics that were revealed through rRNA sequencing. DNA varies significantly across domains, and rRNA sequencing did not show that all DNA is the same across domains. There is no evidence from rRNA sequencing that half of archaeal sequences were previously unknown. rRNA sequencing has been more helpful in understanding relationships between archaea, bacteria, and eukaryotes rather than just prokaryotic species relationships. Archaea are more similar to eukaryotes in many molecular aspects, not more similar to bacteria.

Answer:

that certain nucleic acid sequences are unique to archaea and eukaryotes.