Biology 1002B Lecture Notes - Lecture 5: Lipid Bilayer, Transmembrane Protein, Transporter 2

• School: Western University
• Department: Biology
• Course: Biology 1002B
• Professor: Tom Haffie Denis Maxwell

Document Summary

Fully saturated fatty acids are linear, which allows lipid molecules to pack tightly together. Lipid molecules with one or more unsaturated fatty acids are prevented from packing closely together because of the presence of double bonds introduces kinks in the fatty acid backbone. The more unsaturated fatty acids of the lipid molecules, the more fluid the membrane: relationship of temperature on membrane fluidity. As temperature drops and the random molecular motion of lipid molecules slows down, a point is reached where fluidity is lost and the phospholipid molecules form a semisolid gel. The more unsaturated a group of lipid molecules, the lower the temperature at which gelling occurs. The increased molecular motion may result in membranes becoming too fluid, resulting in a loss of structure. The normal fluid state is with a mixed population of saturated and unsaturated fatty acids: relationship of fluidity to membrane functions such as transport. Electron transport requires molecule to migrate rapidly within the membrane bilayer.