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 ]
This bistability is most obvious in the transition between the follicular and luteal phases, and arises from interactions between positive and negative feedback loops involving GnRH, LH, FSH, estrogen, and progesterone. The kisspeptin system creates a switch-like mechanism driving the transition from negative to positive feedback.
Na + channels both open and close more quickly than K + channels, producing an influx of positive charge (Na +) toward the beginning of the action potential and an efflux (K +) toward the end. Ligand-gated sodium channels, on the other hand, create the change in the membrane potential in the first place, in response to the binding of a ligand ...
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 ...
A negative feedback loop is one that tends to slow down a process, whereas the positive feedback loop tends to accelerate it. The mirror neurons are part of a social feedback system, when an observed action is "mirrored" by the brain—like a self-performed action.
The positive feedback of the rising phase slows and comes to a halt as the sodium ion channels become maximally open. At the peak of the action potential, the sodium permeability is maximized and the membrane voltage V m is nearly equal to the sodium equilibrium voltage E Na .
The hypothalamic–pituitary–thyroid axis (HPT axis for short, a.k.a. thyroid homeostasis or thyrotropic feedback control) is part of the neuroendocrine system responsible for the regulation of metabolism and also responds to stress. As its name suggests, it depends upon the hypothalamus, the pituitary gland, and the thyroid gland.
This dual-origin structure and function are what make the pituitary gland a unique and critical component of the endocrine system, acting as a bridge between the nervous and endocrine systems. 5. Pituitary stem cells: stem cells are found in the pituitary [ 12 ] [ 13 ] which can differentiate into various types of hormone-producing cells in ...