electrochemical gradient

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gradient

 [gra´de-ent]
rate of increase or decrease of a variable value, or its representative curve.
edge gradient in radiology, the penumbra or partial shadow on a radiograph caused by the three-dimensional shape of an object.
electrochemical gradient the difference in ion concentration and electrical potential from one point to another, so that ions tend to move passively along it.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

e·lec·tro·chem·i·cal gra·di·ent

a measure of the tendency of an ion to move passively from one point to another, taking into consideration the differences in its concentration and in the electrical potentials between the two points; commonly expressed as the additional voltage needed to achieve equilibrium.
Farlex Partner Medical Dictionary © Farlex 2012

electrochemical gradient

a trans MEMBRANE gradient formed as a result of the movement of an ION or other SOLUTE across the membrane. This comprises a gradient of electrical charge and a concentration gradient, which depends on the distribution of the ion across the membrane. Such a gradient can be generated by the operation of an ELECTRON TRANSPORT SYSTEM, in the form of a proton motive force (pmf).
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
Herein, we utilize the specific symmetric hour-glass shaped alumina nanochannels with asymmetric ion gradients to adjust diverse surface charge properties in order to develop the asymmetric nanochannel systems that provide variety control over both the pH- and concentration-tunable ionic rectification properties.
In their paper Nick Lane (UCL, Genetics, Evolution and Environment) and Bill Martin (University of Dusseldorf) address the question of where all this energy came from -- and why all life as we know it conserves energy in the peculiar form of ion gradients across membranes.
The SERCA pump is an ~110-kDa transmembrane protein and belongs to the family of P-type ion translocating ATPases, which includes [Na.sup.+]-[K.sup.+]-ATPase and gastric [H.sup.+]-[K.sup.1]-ATPase among others, and are fundamental in establishing ion gradients by pumping ions across biological membranes.
Normally potassium concentration in the extracellular fluid (at rest 4.0-4.5 mM) increases during heavy exercise (Sejersted, 1992), owing to efflux of potassium from muscle fibers exceeding the capacity the sodium-potassium pump to restore ion gradients. This exercise-induced hyperkalemia (e.g., 5-7 mM) may stimulate sodium-potassium pump activity and is probably a key regulator of breathing during exercise.