Introduction to the Human Body: Chapter 1.5 Homeostasis
Are most positive feedback mechanisms homeostatic?
No. The response of this system is an even greater deviation from the set point, creating a cycle that results in death, unless medical intervention occurs.
What is positive feedback?
A self-amplifying cycle in which a physiological change leads to even greater change in the same direction
What is one example of a positive feedback cycle leading to desirable result?
Childbirth
What does the control center do?
It can configure instructions that make any change decrease, bringing it back towards the set point.
What is autoregulation?
It makes use of the body's cells, tissues, and organ systems to make these adjustments. This response to an internal or external conditions is an automatic adjustment. Our bodies are pre-programmed to make this adjustment.
What does negative feedback always functions to do?
Make any deviation from homeostasis, the set point, smaller.
Is negative feedback bad?
No. In fact, it is how most of the body systems maintain 'Homeostasis'.
What does the effector do?
Receives the information about the change from the control center and responds appropriately.
What is extrinsic regulation?
Responses controlled by nervous and endocrine systems
What is necessary for the survival of the human body?
The maintenance of a relatively stable internal environment.
What does the control center know?
The set point and how far a change can deviate from that set point and still have the body function normally.
What happens if the internal environment deviates outside of this homeostatic range?
illness or death will result
What is the function of the sensor?
monitors any change from the set point
In a negative feedback mechanism, the response of the effector
reverses the original stimulus.
What are the three components of a negative feedback loop?
sensor, control center, and effector
What is homeostasis?
the maintenance of a variable around an ideal normal value, or set point.
Homeostasis is the condition produced by
the tendency for change in a body parameter to be counteracted as soon as the body parameter goes past its normal value.