BIOL 121 Lecture Notes - Lecture 4: Positive Feedback, Hypothalamus, Smooth Muscle Tissue
Document Summary
The process by which physiologic variables are kept within a predictable and normal range. How the body maintains a constant environment inside the body no matter the changes going on outside the body. Dynamic constancy- variables may fluctuate over short- term, but are stable over long term. Steady state is the goal (not equilibrium, only time you are in equilibrium is when you"re dead) Change in a variable away from its set point, initiating a responseto bring that variable back towards its set point. Change in a variable away from the set point, causing a chain of events to further increase the change. Does not favor homeostasis locally, but it favors homeostasis for the organism as a whole. The body adjusts to a variable prior to any actual change. Homeostatic reflex links a stimulus to a response (can be either nervous or endocrine mediated) Stimulus- cold temp neurons sense the temp change. Afferent pathway- signal sent to the brain.
