CELL CYCLE It is the series of events that take place in a eukaryotic cell from its formation to its division into two daughter cells. The cell cycle can be divided in two main phases i.e. interphase and the mitosis phase. Interphase This phase lasts for about 90% of the total time of cell cycle. During interphase, the cell performs the life functions according to its specialty and prepares itself for next division. Interphase consists of the following three phases: G1 Phase (First Gap Phase): It starts from the end of the Mitosis phase. It is also called the growth phase. During this phase cell makes proteins and organelles and so grows in size. Cell also makes enzymes that are required in S phase for the replication of DNA. S Phase (Synthesis Phase): During this phase, the DNA of each chromosome is replicated (copied). It results in the duplication of chromosomes (each chromosome consists of two sister chromatids). The total number of chromosomes in cell remains the same.