AP BIOLOGY

Detailed explanation-1: -Homeostatic circuits usually involve negative feedback loops. The hallmark of a negative feedback loop is that it counteracts a change, bringing the value of a parameter-such as temperature or blood sugar-back towards it set point. Some biological systems, however, use positive feedback loops.

Detailed explanation-2: -Negative feedback occurs when a system’s output acts to reduce or dampen the processes that lead to the output of that system, resulting in less output. In general, negative feedback loops allow systems to self-stabilize. Negative feedback is a vital control mechanism for the body’s homeostasis.

Detailed explanation-3: -For example, an increase in the concentration of a substance causes feedback that produces continued increases in concentration. negative feedback loops, in which a change in a given direction causes change in the opposite direction.

Detailed explanation-4: -Negative feedbacks tend to dampen or buffer changes; this tends to hold a system to some equilibrium state making it more stable.

Detailed explanation-5: -Positive feedback intensifies a change in the body’s physiological condition rather than reversing it. A deviation from the normal range results in more change, and the system moves farther away from the normal range. Positive feedback in the body is normal only when there is a definite end point.