(**A)** Newborn L1210 cells were incubated at 37°C. Aliquots of cells were taken every hour from zero to 24 hours to measure the size distribution of the synchronous population as it progress through 2.5 cycles. Proportions of cells at any given size are visualized by color (see color bar at the right). Also shown the time-invariant steady-state distribution of the asynchronous population (right panel). **(B)** The mean linear ,β_{n} , growth constants for each of the time intervals were calculated from and are expressed in fl/hour. Also shown is the distribution of cell cycle stages **(C)**. **(D)** Growth repression visualized from raw size distribution measurements. Size distributions of the synchronized L1210 population are shown for early times in cell cycle just after release from the membrane, The size distribution of newborns (black) is compared with distributions from times *t*=1 hour (red, solid) and times *t* = 2 – 5 hours (red , dashed). There is very little change from time *t* = 0 to time *t* = 1, indicative of the growth repression during the first hour. The larger shifts in the size distribution for later times indicates faster growth later in the cell cycle. **(E)** The mean exponential, *k*_{n}, growth constants for each of the time intervals were calculated from and are expressed in hour^{−1}

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