Interphase is the resting stage of the cell cycle. It covers 95% of the total duration of a cell cycle. It involves a series of changes that prepare a cell for division. It is the period during which the cell experiences growth and DNA replication in an orderly manner. Interphase is divided into three phases.
(i) G1 phase
(ii) S phase
(iii) G2 phase
G1 phase - It is the interval between mitosis and initiation of DNA replication. It is the stage during which the cell grows and prepares its DNA for replication. In this phase, the cell is metabolically active but there is no replication of the DNA.
S phase - It is known as the synthesis phase as it is the stage during which DNA synthesis occurs. In this phase, the amount of DNA (per cell) doubles, but the chromosome number remains the same.
G2 phase - In this phase, the cell continues to grow and prepares itself for the division. The proteins and RNA required for mitosis are synthesised during this stage.
