BSCI 440 Study Guide - Midterm Guide: Tight Junction, Transcytosis, Semipermeable Membrane
15 Sep 2015
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Homeostasis = maintaining a stable environment in the face of environmental. How is it different from stability or equilibrium: Equilibrium is the condition of a system where competing influences are balanced, so. Homeostasis is the ability of a system to adjust its internal environment to maintain a perturbations there is no net change. dynamic steady state. A body is always in osmotic equilibrium, but in chemical and electrical disequilibrium. Molarity = concentration of a solution (number of moles of solute per liter of solution) Osmolarity = how many osmotically active molecules you have in a solution (osm/l) Tonicity = measure of effective osmotic pressure gradient between two solutions separated by a semipermeable membrane. Isotonic = concentrations of each compartment are equal. Describe which one(s) would be used by: a. Large, charged molecules: simple diffusion, facilitated diffusion, active transport, transcytosis. Required concentration gradients:simple diffusion and facilitated diffusion. Used by small, non-polar molecules: simple diffusion.
