Haptotaxis is the directional motility
Motility is a biological term which refers to the ability to move spontaneously and actively, consuming energy in the process. Most animals are motile but the term applies to single-celled and simple multicellular organisms, as well as to some mechanisms of fluid flow in multicellular organs, in...

 or outgrowth of cells, e.g. in the case of axonal outgrowth, usually up a gradient
In vector calculus, the gradient of a scalar field is a vector field that points in the direction of the greatest rate of increase of the scalar field, and whose magnitude is the greatest rate of change....

 of cellular adhesion sites or substrate-bound chemoattractants. These gradients are naturally present in the extracellular matrix
Extracellular matrix
In biology, the extracellular matrix is the extracellular part of animal tissue that usually provides structural support to the animal cells in addition to performing various other important functions. The extracellular matrix is the defining feature of connective tissue in animals.Extracellular...

 (ECM) of the body during processes such as angiogenesis or artificially present in biomaterials where gradients are established by altering the concentration of adhesion sites on a polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...


External links

  • "Cellular Migration" - University of California, Berkeley, 2003. Cell and Tissue Engineering website.
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