One bacterial cell divides by binary fission every 20 minutes. How many cells are there after 3 divisions, starting from one cell?
Answer and explanation
Correct answer: D.
- Step 1: Each division doubles the number of cells.
- Step 2: After 3 divisions: .
Answer
.
Why not the others: : Doubling was treated as adding 2. : The number of divisions was squared. : One division too few was counted.
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