Negative and positive feedback are the factors in a process that drive the system either toward or away from a stable configuration, according to Dictionary.com. One example of a homeostatic process involving negative and positive feedback is the Earth's climate. Homeostasis is the tendency of the system to push back toward a stable state in response to external influences.Know More
Positive and negative feedback are central to an understanding of homeostasis, which About.com describes as one of the unifying principles in the study of biology. Examples include the regulation of the body's temperature, blood pressure and the body's water and electrolyte balance.
Howstuffworks.com describes a mechanical negative-feedback mechanism that was built into early steam engines. The fly-ball governor was a freely rotating set of swing arms with weights attached to their tips and mounted on a threaded post. As steam pressure built up inside the boiler, steam would be forced up the post and cause the arms to swing. As they swung faster, the weighted tips would rise and force open a valve to release steam. This lowered the pressure and brought down the governor's arms, closing the valve again. This is a classic example of negative feedback maintaining a constant pressure. Reversing the effects by closing the valve when the arms rise would be an example of positive feedback in which high pressure induces higher pressure still until the system breaks down.Learn more about Human Anatomy
The nervous system maintains homeostasis by sending electrochemical signals throughout the body, coordinating and executing both the voluntary and involuntary processes that maintain homeostasis, according to Penn Medicine. The nervous system is comprised of fibrous axons, which stretch throughout the body and interconnect to coordinate activity, states Wikipedia.Full Answer >
The immune system maintains homeostasis by preventing pathogens from disrupting the body's normal functioning. It achieves this in various ways, including adaptive immunity when the body encounters a new pathogen, innate immunity, secreting acids onto the skin and using mucus membranes to breakdown bacteria.Full Answer >
The urinary system sustains homeostasis by eliminating wastes from the body, regulating blood acidity levels and controlling the levels of metabolites and electrolytes in the blood, such as sodium, potassium and calcium. The urinary system also maintains a stable internal environment by assisting the osmoregulation of blood volume and pressure.Full Answer >
The primary function of the respiratory system is to provide oxygen to every part of the body through the process of inhaling oxygen and exhaling carbon dioxide. The respiratory system consists of tissues and organs inside the body that allow people to breathe. This system includes blood vessels, the lungs, airways and certain muscles. The major airways of the respiratory system include the nose, windpipe, mouth, bronchial tubes and larynx.Full Answer >