Feedback Systems

Feedback systems are in place to ensure the organisms survival.

- These systems can either be through :

nerve action (nervous system)

hormonal actions (endocrine system).  

- There are two forms of feedback systems

Positive

Negative

Feedback systems are made up of:

The effector will either increase or decrease the intensity of the stimulus, depending on whether the feedback system is positive or negative.

Picks up the disturbance

Processes and interprets the information and acts accordingly.

Aims to enhance or block the stimulus

Negative feedback systems

Negative feedback systems aim to decrease or stop the initial stimulus (That is, they have a negative effect on the stimulus). These systems aims to stabilise the internal environment.

Positive Feedback systems

Positive feedback systems aim to increase or enhance the initial stimulus (that is they have a Positive effect on the stimulus.) An example of this is pregnancy.

Information about the environment is sent from the receptors to the control centre. The control centre then sends out a signal, stimulating a hormonal or nervous systems response. Causing a change in the animal’s behaviour or physiology to decrease the impact on the receptor.

Click here for information on the Endocrine System

Click here for information on the nervous System

We can break receptors up into two main categories:

Misalignment detectors

      These receptors detect precise internal changes. For example CO2 changes in the        blood or body temperature.

Disturbance detectors

      These detect changes in the external and internal environment that could have an        effect on the internal environment. Put simply they detect and warn the body of          the problem before the problem actually arises