Download Feedback Mechanisms

HOMEOSTASIS
&
ORGAN SYSTEMS
Biology
FEEDBACK MECHANISMS
 Living organisms use biochemical pathways in response to
environmental conditions in order to maintain a constant or
stable internal environment
STEPS TO A FEEDBACK MECHANISM
1. Stimulus
 Environmental signal
2. Receptor
 Cell detects change & sends input message
3. Control Center
 Brain interprets & sends output message
4. Ef fector
 Cell receives output message
5. Response
 Behavioral/Chemical change
POSITIVE FEEDBACK
 The product of a process encourages the process
NEGATIVE FEEDBACK
 The product of a process inhibits the process
FEEDBACK & HOMEOSTASIS
HOMEOSTASIS IN PLANTS
 Stomata open/close in response to environmental conditions
HOMEOSTASIS IN ANIMALS
 Pancreas secretes insulin/glucagon in response to blood sugar