Scientific knowledge may change when it is reexamined. For example, scientists in the 1930s proposed changing the way in which organisms were classified. They expanded the number of kingdoms from three to four. The scientists placed the bacteria, which had previously been classified with other single-celled organisms, into this fourth kingdom. What was the main reason for this change in the classification system?
A) Unlike the other single-celled organisms, bacteria lack DNA.
B) Unlike the other single-celled organisms, bacteria lack organelles.
C) Unlike the other single-celled organisms, bacteria reproduce only sexually.
D) Unlike the other single-celled organisms, bacteria are eukaryotes.
Ans: B) Unlike the other single-celled organisms, bacteria lack organelles.
You might also like to view...
The fetal mammal is surrounded by the
A. amnion. B. oviduct. C. ovary. D. All of these answers are true.
The physical characteristics of an organism, or its ________, are determined by its genetic makeup, referred to as its ________
Fill in the blank(s) with correct word
The functional link between cardiac muscle cells is called ____
a. intrinsic pacemakers b. nodes c. intercalated discs d. bundle branches e. extrinsic pacemakers
When a population decreases in number until a small remnant of the original population remains, a ________ has occurred
Fill in the blank(s) with correct word