NTA Abhyas NEET2020BotanyCell Cycle and Cell DivisionPractice
In which phase of the cell cycle, the amount of DNA in a cell remains constant at 4C level, considering that the initial amount of DNA was 2C?
Options
- AG 0 and G 1
- BG 1 and S
- COnly G 2
- DG 2 and M
Correct answer
C. Only G 2
Step-by-step solution
G 1 phase corresponds to the interval between mitosis and initiation of DNA replication. During G 1 phase, the cell is metabolically active and continuously grows but does not replicate its DNA. S or synthesis phase marks the period during which DNA synthesis or replication takes place. During this time, the amount of DNA per cell doubles. If the initial amount of DNA is denoted as 2C, then it increases to 4C. However, there is no increase in the chromosome number; if the cell had diploid or 2n number of chromosome