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)

8

Answer 2

$1\xrightarrow[{}]{{}}2\xrightarrow[{}]{2}4\xrightarrow[{}]{3}8\xrightarrow[{}]{4}16\xrightarrow[{}]{5}5$ $\downarrow 5$ $32\xrightarrow[{}]{6}64\xrightarrow[{}]{7}\underset{\begin{smallmatrix} \downarrow 2 \\\ 256 \end{smallmatrix}}{\mathop{128}}\,$ 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.