∞ generated and posted on 2016.01.17 ∞
Movement directed towards or away from volatile or dissolved substances.
Technically this is movement up or down chemical concentration gradients where the cell (or organism) is able to detect subtle differences in chemical concentration.
is movement away from a given chemical while is movement towards some chemical.
To achieve chemotaxis an organism must possess some degree of polarity, that is, a designated "front" and "back" such that concentration differences between these two ends can be detected.
See also chemotaxis as involved in .