The first cells appeared about ________ billion years ago.
A. 2
B. 5
C. 4.5
D. 1
E. 3.5
Answer: E
Biology & Microbiology
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The E. coli lac operon has ________ operator sequences.
A. four B. two C. three D. one
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Indicate whether the statement is true or false
Biology & Microbiology
Describe the major taxonomic divisions of prokaryotic organisms
What will be an ideal response?
Biology & Microbiology