When cells are metabolically active but not dividing, they are in the lag phase. Lag phase is among the four phases. others being log phase or exponential phase, stationary phase and the death phase, of bacterial growth. During the lag phase there is very little to no bacterial growth, log phase or the exponential phase; the number of cells doubles at a constant rate, stationary phase; the population growth levels off as the rate of cell death equals the rate of cell division, and finally the death phase where the process of cell death is greater than the process of cell division.