This is discrete model of diffusion through a membrane, something like osmosis. Imagine two cells have a total of particles. A particle is selected at random and moved into the other container at each time period, . For the explanation of this concept one can refer to the Figure 6.1 where we consider it to be a discrete time discrete state process:
particles. A particle is selected at random and moved into the other container at each time period, 
. For the explanation of this concept one can refer to the Figure 6.1 where we consider it to be a discrete time discrete state process:
