Video Transcript
In the late 1970s, a six-kingdom
model of classification was proposed. Which of the following kingdoms is
in the six kingdoms but not the five kingdoms proposed by Whittaker? (A) Archaea, (B) Protista, (C)
Monera, (D) Animalia, (E) Plantae.
This question asks about the
difference between six-kingdom and five-kingdom models of classification. So what are these
classifications? Why are they different?
Let’s start by discussing
Whittaker’s system of classification. Robert Whittaker was an American
ecologist that proposed the five-kingdom classification of life in 1969. These kingdoms include Monera,
which includes all prokaryotic life; Protista, which includes eukaryotic unicellular
life and simple cellular colonies; Plantae; Fungi; and Animalia.
In 1977, Carl Woese proposed the
six-kingdom model of classification. This is very similar to that of
Whittaker, with one key difference. Prokaryotic life is divided into
two groups, Eubacteria and Archaebacteria.
In summary, Protista, Fungi,
Animalia, and Plantae are all in both the five- and six-kingdom models of
classification. Woese divided Whittaker’s fifth
kingdom, Monera, into two kingdoms known as Archaea and Eubacteria.
Therefore, the option that
identifies which kingdom is present in the six-kingdom model of classification but
not the five-kingdom model is given by answer choice (A), Archaea.
