The binomial distributions and the indicator of direction of the growing roots

<p><b>.</b> The sample bimodal distribution calculated from the: A. experiment; B. non-random model; and C. model of random growth. Double arrows mark the difference between maxima of bimodal distributions. This difference defines the value of . D. The indicator of direction of the growing roots, , exhibits high variations in the case of non-random growth, both in experiments and numerical simulations, and low variations in the case of random-growth model. The parameter values used in B and C are as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029759#pone-0029759-g003" target="_blank">Fig. 3 B and C</a>, respectively. stands for experiment number.