Homeostasis Flashcards
The ability of the body to maintain a relatively stable (physiologically) internal environment
Homeostasis
It is in a dynamic state of equilibrium and internal conditions vary, but within relatively narrow limits
Internal environment of the body
Variety of factors that act and interact in complex ways to maintain homeostasis
Chemical factors
Thermal factors
Neural factors
Components of homeostatic control mechanism
Variable
Receptor
Control Center
Effector
A factor or event being regulated
Variable
It monitors the environment and responds to changes (the stimuli)
Receptor
It is part of the sensory system and is connected to afferent nerves
Receptor
It determines the set point at which the variable is maintained
Control center
It provides the means to responds to the stimulus
Effector
It is innervated by efferent nerves coming from the brain
Effector
Two types of homeostatic control mechanism
Negative feedback system
Positive feedback system
Output turns down or shut off the original stimulus
Negative feedback system
Enzyme that will be activated in the liver, helping the liver take up excess glucose and store it as glycogen
Glycogen synthetase
Output enhances or turns up the original stimulus
Positive feedback system
Hormone that stimulate uterine contraction during labor
Oxytocin
