title: Diffusion gradients, membrane receptors, and the acquistion of orientational information by cells.
mesh_terms: D001665:Binding Sites; D002462:Cell Membrane / Q000502:physiology*; D002633:Chemotaxis; D004058:Diffusion; D008954:Models, Biological; D011955:Receptors, Drug
chemical_list: D011955:Receptors, Drug