feedback loop

views updated Jun 08 2018

feedback loop (feedback mechanism) A control device in a system. Homoeostatic systems have numerous negative-feedback mechanisms which tend to counterbalance positive changes and so maintain stability. For example, denitrifying bacteria counteract the effects of nitrogen-fixing bacteria. Positive feedback reinforces change and in natural systems may result in radical environmental alteration. For example, an exceptionally cool summer in high mid-latitudes of the northern hemisphere may impede the melting of snow, leading to unusually high albedo, which reduces absorption of solar energy, leading to further cooling, etc.

feedback loop

views updated May 14 2018

feedback loop(feedback mechanism) A control device in a system. Homoeostatic systems have numerous negative-feedback mechanisms which tend to counterbalance positive changes and so maintain stability. For example, denitrifying bacteria counteract the effects of nitrogen-fixing bacteria. Positive feedback reinforces change and in natural systems may result in radical environmental alteration. For example, an exceptionally cool summer in high mid-latitudes of the northern hemisphere may impede the melting of snow, leading to unusually high albedo, which reduces absorption of solar energy, leading to further cooling, etc.