BIOL 1000 Chapter Notes - Chapter 5: Electric Potential, Active Transport, Lipid Bilayer
12 Dec 2016
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Document Summary
Describe the fluid mosaic model of membrane structure. The fluid mosaic model of the membrane structure proposes that: The membrane consists of a fluid lipid bilayer in which proteins are embedded and float freely. This means that membranes are asymmetrical, the halves are not the same. The membrane proteins found on one half of the bilayer are structurally/functionally distinct form the other half. This is important because: lipid bilayer forms structural framework of membranes and serves as a barrier preventing passage of most water soluble molecules. Polar regions of the phospholipids lie at the surface of the bilayer and their non polar tails are in the interior. Passive transport: movement of a substance across membrane without atp energy. Active transport: molecules are moved against their concentration gradient. Maintenance of concentrations (ions=charged, therefore may contribute to electric potential difference: primary active transport: same protein transporting molecules hydrolyzes.
