BIOL 1117 Lecture Notes - Cell Membrane, Transmembrane Protein, Lipid Bilayer

• School: Northeastern University
• Department: Biology
• Course: BIOL 1117
• Professor: Christopher Richardson

Document Summary

Hydrophilic phosphate heads face water on each side of membrane. Hydrophobic tails are directed toward the center, avoiding water: cholesterol, glycolipids. Holds phospholipids still and can stiffen membrane. Phospholipids with short carbohydrate chains on extracellular face. Contributes to glycocalyx: carbohydrate coating on the cell"s surface: membrane proteins, membrane proteins. Hydrophilic regions in contact with cytoplasm and extracellular fluid. Hydrophobic regions pass through the lipids of the membrane. Proteins which are conjugated with short lengths of saccharides that face the extracellular side. *some can drift about freely in phospholipid layer while others are anchored to cytoskeleton: peripheral proteins. Adhere to one face of the membrane. Most peripheral proteins are typically associated with some transmembrane protein: membrane transport, materials pass through the plasma membrane via passive or active mechanisms by carrier-mediated proteins or protein channels, passive transport mechanisms requires no atp. Filtration, diffusion, osmosis: active transport mechanisms uses atp.