Question

How many mitotic divisions must occur in a cell of root tip to form 256 cells.

• A. 256
• B. 8
• C. 128
• D. 64

Answer 1

Answer: (B)

$1\to 2\stackrel{2}{\to }4\stackrel{3}{\to }8\stackrel{4}{\to }16\stackrel{5}{\to }5$ $\downarrow 5$ $32\stackrel{6}{\to }64\stackrel{7}{\to }\underset{\begin{array}{c}\downarrow 2\\ 256\end{array}}{128}$ It can be done with a simple formula ${(2)}^n,$ where n is the number of mitotic, division ${(2)}^n=256$ ${(2)}^8=256(2\times 2\times 2\times 2\times 2\times 2\times 2\times 2=256)$ So, 8 mitotic division.