Question

There are three major, distinct groups of organisms: bacteria, archaea, and eukaryotes. However, until recently bacteria and archaea were considered much more closely related than we know they are today. What is one of the most important ways scientists determined the evolutionary distinctiveness of these three groups?

Answer 1

Answer:

Comparative genomics of the three groups

Explanation:

The comparative genomics of the three groups was used to determine their evolutionary distinctiveness. Comparative genomics is a powerful tool used to study evolutionary changes among organisms, it helps to identify gene similarities and differences among organisms.  

Bacteria and archaea (formerly called archaebacteria)  were considered much more closely related, but DNA sequence analysis showed numerous differences between the two groups, and further proved that archaea was closely related to eukarya than bacteria.

However, in 1970, Dr. Carl Woese and other scientists in a bid to determine the distinction between the three groups made use of the nucletide sequence of the ribosomal RNA as an evolutionary time clock.

It is widely known that the rRNA sequences; is present in all organisms, functions differently in various organisms, is involved in protein synthesis, can be align between two organisms and can change gradually over a long period, hence this made it a good tool to determine evolutionary distinctiveness.