Search results
Results from the WOW.Com Content Network
A feedback loop where all outputs of a process are available as causal inputs to that process. Feedback occurs when outputs of a system are routed back as inputs as part of a chain of cause-and-effect that forms a circuit or loop. [ 1] The system can then be said to feed back into itself. The notion of cause-and-effect has to be handled ...
Positive feedback (exacerbating feedback, self-reinforcing feedback) is a process that occurs in a feedback loop which exacerbates the effects of a small disturbance. That is, the effects of a perturbation on a system include an increase in the magnitude of the perturbation. [1] That is, A produces more of B which in turn produces more of A. [2]
In biochemistry and pharmacology, receptors are chemical structures, composed of protein, that receive and transduce signals that may be integrated into biological systems. [1] These signals are typically chemical messengers [nb 1] which bind to a receptor and produce physiological responses such as change in the electrical activity of a cell.
In that case you have a feedback system, and the block labeled System in Figure(c) is a feed-forward system. In other words, systems of different types can be nested, and the overall system regarded as a black-box. Feedforward control is distinctly different from open loop control and teleoperator systems. Feedforward control requires a ...
Chemotaxis is described in prokaryotic and eukaryotic cells, but signalling mechanisms (receptors, intracellular signaling) and effectors are significantly different. Durotaxis is the directional movement of a cell along a stiffness gradient. Electrotaxis (or galvanotaxis) is the directional movement of motile cells along the vector of an ...
The types of barriers that can cause this isolation include: different habitats, physical barriers, and a difference in the time of sexual maturity or flowering. [6] [7] An example of the ecological or habitat differences that impede the meeting of potential pairs occurs in two fish species of the family Gasterosteidae (sticklebacks).
Allee effects are classified by the nature of density dependence at low densities. If the population shrinks for low densities, there is a strong Allee effect. If the proliferation rate is positive and increasing then there is a weak Allee effect. The null hypothesis is that proliferation rates are positive but decreasing at low densities.
Contact inhibition is a regulatory mechanism that functions to keep cells growing into a layer one cell thick (a monolayer). If a cell has plenty of available substrate space, it replicates rapidly and moves freely. This process continues until the cells occupy the entire substratum. At this point, normal cells will stop replicating.