[Campbell Biology P.635] Which statement accurately describes the recent findings regarding ... | Practice Question

Which statement accurately describes the recent findings regarding archaeal phylogeny mentioned in the text?

  • A: The TACK supergroup includes Euryarchaeota, Crenarchaeota, Thaumarchaeota, and Aigarchaeota.
  • B: Lokiarchaeotes are considered the long-sought sister group of the eukaryotes and are closely related to TACK archaea.
  • C: Metagenomic studies suggest that Euryarchaeota and Crenarchaeota are the only archaeal clades that contain extremophiles.
  • D: Thaumarchaeota, Aigarchaeota, and Korarchaeota are more closely related to Euryarchaeota than to Crenarchaeota.

Explanation

The text explicitly states: 'The importance of the TACK supergroup was highlighted by the recent discovery of the lokiarchaeotes, a group that is closely related to TACK archaea and that may represent the long-sought-after sister group of the eukaryotes.' This directly supports option B. Option A is incomplete, as Korarchaeota is missing. Option C is incorrect because the text mentions many euryarchaeotes and crenarchaeotes are not extremophiles. Option D is incorrect as the text states these groups are 'more closely related to the Crenarchaeota than they are to the Euryarchaeota.'