Question

Select the correct option:

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?

• A. 21 minutes
• B. 23 minutes
• C. 60 minutes
• D. 160 minutes

Answer 1

Answer: (B)

23 minutes

In $20$ mins, culture tube is $1/8th$ 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 $\frac{1}{4}\times 2=\frac{1}{2}$

In $23$min $\frac{1}{2}\times 2=1$

That means in 23 minutes, the culture tube will be completely filled.

So, the correct answer is '23 minutes'.