Search results
Results From The WOW.Com Content Network
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 ]
Thyrotropic feedback control on a more detailed and quantitative level. [3] Thyroid homeostasis results from a multi-loop feedback system that is found in virtually all higher vertebrates. Proper function of thyrotropic feedback control is indispensable for growth, differentiation, reproduction and intelligence.
The interaction between the two types of loops is evident in mitosis. While positive feedback initiates mitosis, a negative feedback loop promotes the inactivation of the cyclin-dependent kinases by the anaphase-promoting complex. This example clearly shows the combined effects that positive and negative feedback loops have on cell-cycle ...
Schematic of the HPA axis (CRH, corticotropin-releasing hormone; ACTH, adrenocorticotropic hormone) Hypothalamus, pituitary gland, and adrenal cortex The hypothalamic–pituitary–adrenal axis (HPA axis or HTPA axis) is a complex set of direct influences and feedback interactions among three components: the hypothalamus (a part of the brain located below the thalamus), the pituitary gland (a ...
The Hodgkin cycle represents a positive feedback loop in which an initial membrane depolarization leads to uncontrolled deflection of the membrane potential to near V Na. The initial depolarization must reach or surpass a certain threshold in order to activate voltage-gated Na + channels .
The activation of Mos leads to a positive feedback loop and therefore acts as “toggle switch” to create the all-or-nothing entrance into mitosis. Schematic of the MAPK signaling cascade. This feedback loop was first found by showing that MAPK-P (phosphorylated MAPK) concentrations increased in response to increasing levels of progesterone. [24]
Feedback mechanism might involve negative and positive feedbacks. In the negative feedback, the pathway is inhibited and the result of the transduction pathway is reduced or limited. In positive feedback, the transduction pathway is promoted and stimulated to produce more products.
Bistability can be generated by a positive feedback loop with an ultrasensitive regulatory step. Positive feedback loops, such as the simple X activates Y and Y activates X motif, essentially link output signals to their input signals and have been noted to be an important regulatory motif in cellular signal transduction because positive ...