Domain Kingdom Both?

Question 1

What theory did scientists investigate further and how?

Answer 1

How eukaryotes may have evolved from prokaryotes

Using the techniques of molecular phylogeny

Question 2

How did scientists investigate this theory, via molecular phylogeny?

Answer 2

They have looked at the internal structure of the prokaryotes and eukaryotes and compared them to the biochemistry of the proteins involved in their ribosomes and enzymes

Question 3

What did much of this analysis involve?

Answer 3

The use of bioinformatics to process the masses of data generated

Question 4

What was the new theory that was developed?

Answer 4

There are three domains:
Two prokaryotic domains
The archae
The bacteria

Question 5

What has studies shown about these three domains?

Answer 5

Probably had a single common ancestor around three billion years ago

Question 6

What has evidence shown about the Archae?

Answer 6

Some evidence suggests the archae are more closely related eukaryotes, including us , than the bacteria

Question 7

Scientists have found two key differences in the mass of data that has been generated about the three domains…

Answer 7

1. Archae replicate by binary fission controlled within a cell cycle, which seems homologous to the cell cycle in eukaryotic cells but is rather different from replication in bacteria
2. On the other hand, the membrane structure and the membrane proteins of archae are unique- they’re different from the bacteria and eukaryotes, which have homologous structures

Question 8

What does an archae contain and how di=oes it benefit it?

Answer 8

The archaea have an ether link in their lipids, giving branched molecules that may provide extra strength in extreme environments