Homeostasis Flashcards
Hierarchy of human body
Chemicals
Cells
Tissues
Organs
Systems
How much of the adult body is fluid ?
60%
How much fluid within cells ?
70%
How much fluid outside cells ?
30%
Homeostasis
Physiological systems maintain a relatively stable environment in a fluctuating environment.
Control system types
Open loop
Closed loop
Feedforward
Open loop
No feedback
Could result in run-away reactions
Closed loop
Output of system feeds back and influences controller
Feedforward
Response in generated in anticipation of change
ANTICIPATES CHANGE
Negative feedback
Returns to a set point
PROMOTES STABILITY
Positive feedback
Moves away from a set-point
PROMOTES A CHANGE IN ONE DIRECTION
Gain
Correction / Error
Degree of effectiveness of a negative control system
Example of feedforward control
Body preparing for digestion