BIOL 361 Lecture 1: Lecture one bio 361 notes
Document Summary
Predict if and how a molecule will cross a cell membrane, considering the properties of both the membrane and the molecule: Cell membrane properties: made up of lipids and proteins. Bonds: electrostatic/hydrogen between polar heads and water. Van der waals (weak) between non-polar tails allow lateral movement of lipids and proteins within membrane. Will something cross the cell membrane: properties of membrane: fluidity. Fluidity increases with temperature since vander waals weaken. Fluidity increases with more shorter fatty acid tails. Fluidity increases when more unsaturated: properties of molecule: polarity and charge. Explain why the cell membrane is selectively permeable, based on the structure and function of membrane transport proteins: Protein function: used to diffuse across lipid bilayer for molecules that don"t diffuse freely or don"t diffuse or against gradient. Protein structure: protein domains are a ring that form a pore. Pore is lined with amino acids with specific charges. Selectivity filter: based on size, charge, and charge density.
