In the three-domain system of classification
A) eukaryotes are more similar to the prokaryotes now classified in domain Bacteria than to those now classified in domain Archaea.
B) animals and plants are less similar to each other than to the prokaryotes now classified in domain Archaea.
C) prokaryotes are classified into two domains, with the organisms in domain Archaea more similar to eukaryotes than to the prokaryotes in domain Bacteria.
D) cladistics alone are used to formulate the new phylogenetic tree of life.
E) by the principle of parsimony, it requires fewer assumptions to divide the prokaryotes into two domains than it does to put them in a single domain. Analysis of rRNA genes indicate that some prokaryotes, now classified as the domain Archaea, are more similar to eukaryotes than to the other prokaryotes that are now classified in the domain Bacteria.

Question

Quizplus · Accepted Answer

The three-domain system of classification separates prokaryotes into two domains: Bacteria and Archaea, with eukaryotes belonging to a third domain. Analysis of rRNA genes has shown that some organisms in domain Archaea are more closely related to eukaryotes than to other prokaryotes in domain Bacteria. Therefore, option A is incorrect. Option B is incorrect because animals and plants are both eukaryotes, while Archaea is a separate domain altogether. Option D is incorrect because while cladistics is used in formulating phylogenetic trees, it is not the only method used. Option E is true but not the best choice since it does not reflect the complete picture of the three-domain system of classification.

In the Three-Domain System of Classification