Homeostasis Flashcards
Provide an explanation as to what homeostasis is
Homeostasis can be described as being a state of relative balance among the body’s numerous regulatory systems. These systems assist in detecting change in the internal environment and help carry out functions to keep the body stable in dynamic equilibrium
Provide at least two examples of bodily functions regulated by homeostasis
Examples of functions in the body regulated by homeostasis include body temperature, pH levels, blood glucose levels, and blood pressure
Name the 5 main parts of a feedback loop
Stimulus, Receptor, Control Centre, Effector, Response
What is a stimulus?
A stimulus produces change in a variable
What is the function of a receptor?
The receptor detects change and sends the information to the control centre
Describe the function of the control centre
The control centre analyses the information and regulates a response
What is the function of an effector?
The effector carries out the response from the control centre
What is a response?
The response is a change in that same variable which stabilises homeostasis in the body
What is a positive feedback loop?
A positive feedback loop is a system that perpetually increases a change in the body, in response to a particular stimulus, until an endpoint is reached. It is known to be a self-amplifying cycle
Provide an example of a positive feedback loop.
An example of a positive feedback loop is the clotting of blood when cut. In this example, when a blood vessel is injured it releases a chemical which attracts platelets. These platelets then adhere to the site of injury and release more of that same chemical. This cycle continues until the wall of the blood vessel is patched and the chemical is no longer produced.
What is a negative feedback loop?
A negative feedback loop senses a change in the body and uses the body’s systems to inhibit the effects of the initial change, returning to equilibrium. This feedback loop stops once the change in that specific parameter reaches the set (normal) value.
Provide an example of a negative feedback loop
An example of a negative feedback loop is the monitoring of body temperature.
* Stimulus: body temp exceeds 37C
* Receptor: thermoreceptors in internal environment
* Control centre: hypothalamus sends info to sweat glands
* Effector: Sweat glands produce sweat and bring down body temp
