Dimensionality, compartmentalized systems chemical reaction efficiency

Having confirmed that the concept of reduction of dimensionality can play an important role in determining the efficiency of diffusion-controlled reactions in both symmetrical and asymmetrical compartmentalized systems, one may ask How does a substrate know, upon first encounter with the boundary, to move along the interior surface of a cellular unit, to react (eventually) with (say) a membrane-bound enzyme While substrate-specific, surface binding or association forces can conspire to keep the substrate in immediate vicinity of the boundary, once the latter has been encountered for the first time, certain (chemically) nonspecific, statistical factors are also likely to play a role in reduction of dimensionality. 

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