Q25 / 180 · JIPMER 2015 · Botany

The mitotic cell cycle is divided typically into four phases: $\mathrm{G}_1, \mathrm{~S}, \mathrm{G}_2$ and M . Considering a mitotic cycle time of 18 hrs ; the distribution of period of time (in hrs) for each of these phases will be

  • A
    $\begin{array}{cccc}\mathrm{G}_1 & \mathrm{~S} & \mathrm{G}_2 & \mathrm{M} \\ 1 & 3 & 5 & 9\end{array}$
  • B
    $\begin{array}{cccc}\mathrm{G}_1 & \mathrm{~S} & \mathrm{G}_2 & \mathrm{M} \\ 9 & 1 & 3 & 5\end{array}$
  • Correct answer
    C
    $\begin{array}{cccc}\mathrm{G}_1 & \mathrm{~S} & \mathrm{G}_2 & \mathrm{M} \\ 9 & 5 & 3 & 1\end{array}$
  • D
    $\begin{array}{cccc}\mathrm{G}_1 & \mathrm{~S} & \mathrm{G}_2 & \mathrm{M} \\ 3 & 5 & 9 & 1\end{array}$

Solution

The longest phase of cell cycle is $\mathrm{G}_1$ where these rapid growth and metabolic activity, followed by S phase for DNA synthesis and replication then $\mathrm{G}_2$ phase for preparation of cell division and lastly mitotic phase. $\therefore$ Ratio is $9: 5: 3: 1$

Hence, the correct answer is option: 'C'.

Relevant Questions