PSYC 2410 Lecture Notes - Lecture 9: Peripheral Membrane Protein, Cell Membrane, Hydrophile

• School: University of Guelph
• Department: Psychology
• Course: PSYC 2410
• Professor: Boyer Winters

Document Summary

Phospholipid polar head (glycerol phosphate) hydrophilic: water-loving two nonpolar fatty acid tails hydrophobic: water-fearing. Nonpolar areas form a hydrophobic region between the hydrophilic heads. At body temperatures the interior of the bilayer is fluid. Lipids of membrane form a barrier to hydrophilic (water soluble) molecules. Movement of substance (liquid or gas) along a concentration gradient. Concentration gradient and electrostatic pressure act together to determine distribution of ions . Membrane potential: difference in electrical charge between the inside and the outside of a cell (related to uneven distribution of ions and proteins across the membrane) Sodium: na+ potassium: k+ chloride: cl- protein ions - Cell membrane !!!! not equally permeable to all ions. Experiments by alan hodgkin and andrew huxley (1950) They calculated the electrostatic charge needed to keep the various ions in the location where, at rest, they are in greater concentration: 70 mv - 70 mv = 0 (resting potential: - 70 mv)