BSCI 105 Lecture Notes - Lecture 9: Lipid Bilayer, Extracellular Matrix, Golgi Apparatus

• School: University of Maryland
• Department: Biological Sciences Program
• Course: BSCI 105
• Professor: Norma Allewell

Document Summary

Effect of unsaturated fatty acids and cholesterol on membrane fluidity: cholesterol reduces fluidity at moderate temperatures, prevents solidification at high temperatures, unsaturated fats increase membrane fluidity, cells adjust composition of fats to maintain homeostasis. Phospholipids move: it is easy for lipids to move side to side. Lateral movement occurs ~107 times per second. Membrane proteins are embedded in the lipid bilayer. ~1x per month: hydrophobic regions of protein are in the middle of the membrane, hydrophilic regions of proteins are on the inside and outside of the membrane. Current model of animal cell plasma membrane: glycolipid are sugars attached to the phospholipid. Communicate what type of cell it is. Polysaccharides allow for most diversity: fibers of extracellular matrix. Structure of transmembrane protein: proteins are alpha helixes, terminus are on the outside and inside of cell. Membrane components are synthesized in endoplasmic reticulum and golgi apparatus: polysaccharide groups are added to groups in the er.