Homeostasis and Feedbacks Systems Background Information When a change in one variable causes other parts of a system to change, and this in turn creates further changes to the initial variable, it is called a feedback. In the figure below, the initial change is represented as the size of the box changing (step 1). This change interacts with other parts (step 2), which in turn cause the size of the box to change again (step 3). The initial change (step 1) can be an increase (a, c) or a decrease (b, d). A positive feedback exists when the initial change get exacerbated: In (a) the initial increase gets magnified, in (b) the initial decrease leads to a further reduction. Both (a) and (b) represent positive feedbacks, and cause the system to move further away from the starting point. A negative feedback exists when the initial change gets counteracted. In (c) the initial increase is followed by a decrease, while in (d) the initial decrease is followed by an increase. Both (c) and (d) represent negative feedbacks, and cause the system to return to its starting point. Apply