dm=dm omk, m+p Dm-1 umts (membrane protein. lipid) OX D 100 umts (cytosolic small molecule) For a second messenger to establish and maintain a Images removed due to copyright considerations See Postma. M. and P.j. van hastert gradient the dispersion a diffusion-translocation model for gradient sensing rangeλ should be smaller by chemotactic cells. "Biophys J.81, no. 3(Sep, 2001): 1314-23. than cell size kk m P x m D dt dm m − + ∂ ∂ = 2 −1 2 Dm ~ 1 µm2s-1 (membrane protein. lipid) Dm ~ 100 µm2s-1 (cytosolic small molecule) For a second messenger to establish and maintain a gradient the dispersion range λ should be smaller than cell size Images removed due to copyright considerations. See Postma, M., and P. J. Van Haastert. "A diffusion-translocation model for gradient sensing by chemotactic cells." Biophys J. 81, no. 3 (Sep, 2001): 1314-23. L m k s k Dm µ λ 10 1 1 1 1 = = = − − − 2