homeostasis

maintenance of a constant state within a living organism definition maintenance of a constant state within a living organism

Control systems needed to achieve this have the following: Sensor / Receptor to monitor the factor to be controlled Corrective mechanism to bring about changes to regulate the factor Negative feedback mechanism to stop the corrective process and prevent over-correction

change from ‘norm’ level (excess) ‘norm’ ‘norm’ change from Corrective mechanism. Effectors bring about a return to ‘norm’ detected by receptors change from ‘norm’ level (excess) ‘norm’ ‘norm’ Corrective mechanism. Effectors bring about a return to ‘norm’ change from ‘norm’ level (deficiency) detected by receptors

Each system needs DIFFERENT mechanisms to raise/lower the factor Each system needs DIFFERENT mechanisms to raise/lower the factor. This causes the factor to fluctuate about a norm. The process is called NEGATIVE FEEDBACK

In homeostasis, deviation from the norm acts as the signal that sets off the corrective mechanism. This negative feedback keeps variable factors within the narrow ranges suitable for life.

and returns the factor towards its norm any change from the norm is a deviation. The deviation acts as a signal to the control centre level of factor deviations outside the norm may not be controlled by homeostasis this is the range of this factor that can be controlled by homoeostasis. Cells work well within this range Control centre sets off the correct response response cancels out the deviation and returns the factor towards its norm This is the norm or set point for the homeostatic control system. This would be the ideal level of this factor for cells to work

and returns the factor towards its norm any change from the norm is a deviation. The deviation acts as a signal to the control centre level of factor deviations outside the norm may not be controlled by homeostasis this is the range of this factor that can be controlled by homoeostasis. Cells work well within this range Control centre sets off the correct response response cancels out the deviation and returns the factor towards its norm This is the norm or set point for the homeostatic control system. This would be the ideal level of this factor for cells to work

and returns the factor towards its norm any change from the norm is a deviation. The deviation acts as a signal to the control centre level of factor Control centre sets off the correct response response cancels out the deviation and returns the factor towards its norm

and returns the factor towards its norm any change from the norm is a deviation. The deviation acts as a signal to the control centre level of factor Control centre sets off the correct response response cancels out the deviation and returns the factor towards its norm