Homeostasis Flashcards
define homeostasis
maintaining relatively constant conditions despite constant changes in the external environment
how many mechanisms of regulation are there for homeostasis?
5
name the 5 mechanisms of regulation
(1) autoregulation
(2) control centre
(3) receptor
(4) extrinsic regulation
(5) effector
what is the function of autoregulation?
automatic response in a cell, tissue, or organ to some environmental damage
What is the function of the control centre?
processes the signal and sends instructions
what is the function of the effector?
carries out instruction
what is the function of the receptor?
receives the stimulus
what is the function of the extrinsic regulation?
responses controlled by nervous and endocrine systems
why is the set point used?
designed value or range of a biological variable
what is a receptor?
a body structure that monitors changes in a controlled condition and sends input to a control centre.
define some roles of positive feedback
-used to speed up processes
-response of the effector increases change of the stimulus
-body is moved away from homeostasis
what is the role of anticipatory mechanisms?
with the expectation that stimuli would modify the set up point of a biological parameter
define some roles of negative feedback
-The response of the effector regulates the stimulus
-the body is brought back into homeostasis
what feedback is received at the cellular and molecular level, what are the outcomes?
- cells express receptors upon the surface
- maintenance of biological processes activated by receptors at set-up point
when feedback fails, what are the outcomes?
-often result in disease
-through loss of biological signals or persistent and improper activation
-occurs in both positive and negative feedback system
