Physiology 2130 Lecture Notes - Lecture 3: Electrochemical Gradient, Lipid Bilayer, Extracellular Fluid

• School: Western University
• Department: Physiology
• Course: Physiology 2130
• Professor: Christine Bell

Document Summary

Cell membrane allows for there to be a difference between the interstitial fluid and the intracellular fluid. Ions differences: concentration are maintained due to the fact that the membrane is semi-permeable and does not allow molecules to cross the membrane at any time or for any reason. Different mechanisms by which molecules can cross a membrane. Diffusion: not a passive process, passive doesn"t require atp, movement of molecules form high to low concentration, molecules that are not lipid soluble will not cross the membrane. Won"t cross the lipid membrane so they need a channel or pore. Different mechanism to get into the cell. Osmosis: movement of water from high to low concentration, form of diffusion, passive, no atp required, water cannot cross the membrane requires specific channels/pore aquaporines to allow water to come in. Facilitated diffusion: different channels in the membrane that allow solute to cross along their.