BIOL 1090 Lecture Notes - Lecture 3: Glucose Transporter, Active Transport, Integral Membrane Protein

• School: University of Guelph
• Department: Biology
• Course: BIOL 1090
• Professor: Andrew Bendall

Document Summary

All membranes share common properies: ~6nm thick(with associated water, stable, lexible, capable of self assembly(ex. Liposomes) can be used to deliver drug into animal"s system-if unrecognized by cell. Membranes have diferent funcions, in diferent cells & within an individual cell: diferent areas of the plasma membrane perform diferent funcions. Lipid movement to other lealet is slow. Diferent membranes contain diferent types of lipids and proteins. Lipid rats are small areas of the plasma membrane that are enriched in certain types of lipids. May form funcional compartment (nature/funcion of rats is controversial) Lipid bilayer do not allow many compounds to pass through them freely. Small, uncharged molecules cross membranes relaively easily (o2, co2, no, h2o) Large/polar/charged compounds cannot easily cross lipid bilayers. Speciic mechanisms exist for the controlled transport of many substances across membranes. 4 basic mechanisms for moving molecules across membranes. Simple difusion (passive, nonmediated: very small molecules, uncharged, down a concentraion gradient (low is downhill)