PHSI 208 Lecture Notes - Lecture 7: Nucleoid, Glycogen, Endoplasmic Reticulum
Document Summary
Body fluid compartments: the ecf and icf are in osmotic equilibrium but have very different chemical composition, fluid concentration are equal; the amount of solute per volume solution, ecf is 1/3 of the total body water volume. Icf is 2/3 of the total body water volume. Interstitial fluid lies between the circulatory system and the cells. 1l ~ 1kg, 42 of 70 kg is water, 60% of the body is water. 14 l ecf: plasma 25%, interstitial fluid 75% The movement of water across a membrane in response to a solute concentration gradient is called osmosis: water can move freely between the intracellular and extracellular spaces, aquaporin channels: Involved in short term and long term water regulation of water balance: osmotic equilibrium does not equal chemical or electrical equilibrium, the body compartments are in a state of chemical disequilibrium. The cell membrane is a selectively permeable barrier between the ecf and icf.
