Figure 4.

Examination of noisy partitioning due to low particle numbers. (a) Frequency of null transfer to the bud (or, equivalently, complete retention in the mother) for different total particle numbers N_T as a function of the forward transfer efficiency α, with β = 3α/2 (i.e., along the red line shown in Figure 3). The upper x-axis is expressed in terms of diffusion constant, assuming typical values for yeast budding of σ = 2/3, R = 2.5 μm, d = 1.25 μm, and T = 90 min (from Zhou et al. [18]). (b) Null transfer frequency phase space. Phase space of the logarithm (base 10) of the final mother fraction, log x, corresponding to the bud fraction, y = 1 − x, displayed in Figure 3a. The frequency of null transfer is $f=x^{N_T}$ or log f = N_T log x. The logarithm of f can therefore be efficiently obtained for a given N_T by its product with the displayed log x for any value of α and β. The solution phase space is color-coded from low (purple) to high (blue) logarithm of the final mother fraction.