BIOL1040 Lecture Notes - Lecture 1: Signal Transduction, Exocytosis, Close-Packing Of Equal Spheres
Document Summary
Module 1 lecture 1: membrane structure and function 1. How do we know it is a fluid mosaic: experiment, labelled proteins of mouse and human cells fusion of cells mixed proteins. Six major functions of membrane proteins: transport, enzymatic activity, signal transduction, cell-to-cell recognition, attachment to cytoskeleton and extracellular matrix. Selective permeability: membrane structure lipid bilayer selective permeability, permeable to water, oxygen, carbon dioxide. Impermeable to charged ions, glucose, macromolecules (proteins, rna) essential. Module 1 lecture 2: membrane structure and function 2. Passive transport: diffusion/osmosis, does not require atp, concentration equilibrium elimination of gradients, down concentration gradient (high conc low conc) Osmosis: diffusion of water to region with higher solute concentration equal concentrations. Tonicity ability of a solution to cause a cell to gain or lose water. Isotonic solution equal concentrations no net movement of water: hypertonic solution solute concentration greater outside cell cell loses water, hypotonic solution solute concentration greater inside cell cell gains water.
