chemotaxis

Definitions

  • WordNet 3.6
    • n chemotaxis movement by a cell or organism in reaction to a chemical stimulus
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Webster's Revised Unabridged Dictionary
    • Chemotaxis (Biol) The sensitiveness exhibited by small free-swimming organisms, as bacteria, zoöspores of algæ, etc., to chemical substances held in solution. They may be attracted (positive chemotaxis) or repelled (negative chemotaxis).
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Century Dictionary and Cyclopedia
    • n chemotaxis The locomotion of organisms or of cells in relation to chemical substances, or the property of certain chemical substances to attract or repel living cells at the point of action: in the first instance there is positive chemotaxis, in the second negative chemotaxis. The peculiar response of the white blood-corpuscles to chemotactic stimulation is of fundamental importance in the defense of the animal organism against bacterial invasion.
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Etymology

Webster's Revised Unabridged Dictionary
Chem,ical + Gr. arrangement, fr. to arrange

Usage

In literature:

Carter, H.J., on reproduction of lower animals and foreshadowing of Chemotaxis.
"More Letters of Charles Darwin Volume II" by Charles Darwin
The law of chemotaxis will explain it.
"Valere Aude" by Louis Dechmann
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In news:

Possible Cooperation of Differential Adhesion and Chemotaxis in Mound Formation of Dictyostelium.
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In science:

Chemotaxis is frequently observed in microorganisms.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
In other words, the existence of memory in the internal state makes chemotaxis possible.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
However, this is true only for short-term behavior of chemotaxis.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
All simulations for other parameters show that the elements assemble in the region x ≥ 0, that is, the chemotaxis works well for τs <∼ τ ∗ <∼ τa .
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
Now, ˜τs , the threshold beyond which the (renormalized) Oosawa condition ˜τs <∼ τ ∗ is satisfied, is expected to give a criterion for chemotaxis.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
By changing the internal timescales τs and τa , we have examined the validity of the Oosawa condition for chemotaxis.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
Whether chemotaxis works efficiently is determined by the Oosawa condition for both the chemical concentration field of a stepfunction and a constant slope, and both for short- and long-term behavior.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
The fraction 0.5 indicates the absence of chemotaxis in short-term behavior.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
In contrast, response of the tumbling frequency without adaptation causes the long-term behavior of cells to be represented by a random walk, so that chemotaxis is not possible.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
Clark and Grant recently reported the conditions for the internal response function R(t) to show chemotaxis.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
In general, the conditions for short- and long-term chemotaxis differ, but by imposing some type of optimization to balance the two behaviors, they were able to obtain a certain condition for the response function, which implies the existence of a form of memory in the autocorrelation function.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
Our work answers the question about why chemotaxis requires dynamics.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
By assuming a class of intracellular dynamics, we have shown that chemotaxis occurs in both short- and long-term behavior without requiring an optimization condition, provided that the Oosawa condition is satisfied.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
Because short- and long-term chemotactic behaviors are satisfied simultaneously, one expects that cells can choose such internal adaptation dynamics that enable efficient chemotaxis for a variety of external conditions.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
Here we have demonstrated chemotaxis in the two cases: with a constant slope and with a stepwise change.
On a Condition for Intracellular Adaptive Dynamics for Chemotaxis
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