The Organisms Formerly Classified in the Kingdom Protista ________

Question

The organisms formerly classified in the Kingdom Protista ________.
A) all contain chloroplasts
B) form a single monophyletic group
C) include the last universal common ancestor (LUCA) of life
D) are scattered throughout all branches of the eukaryote family tree
E) have a fossil record extending back 3.4 million years

Accepted Answer

The organisms formerly classified in the Kingdom Protista are scattered throughout all branches of the eukaryote family tree. They are a diverse group of eukaryotic organisms and do not form a single monophyletic group. Some Protists contain chloroplasts, while others do not. It is unlikely that the last universal common ancestor (LUCA) of life was a protist, as protists are only one group of eukaryotes and LUCA was probably a simpler organism that predates the evolution of eukaryotic cells. Protists do not have a fossil record extending back 3.4 million years, as this time frame is relatively recent in the history of life on Earth.