Given below is a schematic break-up of the phases/stages of cell...

Cell cycle completes in two steps- Interphase and M-phase. Interphase is completed in three successive stages $\mathbf{G}_1$-phase (post mitotic phase), S-phase (synthetic phase)$and \mathbf{G}_2$-phase (pre-mitotic or post synthetic phase). In the given figure, $\mathrm{D}$ is representing the S-phase (synthetic phase) of cell cycle.