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Q.
A cell's division time is $1$ minute. In $20$ minutes, a culture tube (culture medium) is $1/8^{th}$ filled with cells. When the tube will be fully filled?
Cell Cycle and Cell Division
Solution:
In $20$ mins, culture tube is $1 /8^{th}$ filled with cells. Each cell divides every minute producing two daughter cells.
Hence, in $21$ min $ = \frac{1}{8} \times 2 = \frac{1}{4}$
In $22$ min $\frac{1}{4} \times = \frac{1}{2}$
In $23$ min $\frac {1}{2} \times 2 = 1$
That means, in $23$ minutes, the culture tube will be completely filled.