Geology GEOL-G 107 Lecture Notes - Lecture 99: Vascular Organ Of Lamina Terminalis, Angiotensin, Preoptic Area
Document Summary
Homeostasis: regulation of a physiological variable within narrow limits that the body requires (term from walter cannon) Achieved by physiological means and behavioral means e. g. , body temperature: Hunger = stomach contractions; study cannon and washburn. B356 lecture 12 intravascular fluid (blood plasma) interstitial fluid (between the cells) cerebrospinal fluid. Body water compartments: intracellular fluid (inside cells) 2/3 of body water extracellular fluid (outside cells) are different mechanisms to regulate intracellular and extracellular compartments. The amount of fluid in the cells is determined by the concentration of solutes (na+ most important) outside the cells. H2o molecules move so concentration of h2o is the same inside and outside cells (osmosis) Normally the extracellular fluid is isotonic with the intracellular fluid (i. e. , concentration of solutes the same inside and outside) If the extracellular fluid loses water (becomes more concentrated with na+; hypertonic) water will diffuse out of the cell. This is the signal for intracellular (osmometric) thirst.
