BI110 Lecture 14: BI110-Lecture 14- Cell Membranes (Module 17 cont’d) & Membrane Transport (Module 18)
Document Summary
Bi110-lecture 14- cell membranes (module 17 cont"d) & membrane transport (module 18) Next late nite lab (cellular respiration) due november 12th. If the temperature drops low enough, phospholipids molecules become closely packed, and membrane forms highly viscous (less fluid)semi solid gel. At low temperatures = enzymes and proteins cannot function if fluidity is not maintained. At high temperatures = too much fluid to cause leakage. Sterols are membrane buffers (maintains fluidity to a variety range) Proper fluidity can be maintained over a broad range of temperatures by adjusting fatty. Desaturases: acid composition of the phospholipids introducing the double bonds in the structure. Enzymes that produce unsaturated fatty acid during fatty acid synthesis, Regulation of desaturases allows for organisms to closely regulate amount of unsaturated fatty acids and membrane fluidity. Passive membrane transport (with normal diffusion and simple diffusion): Hydrophobic nature of membranes restricts free movement of many molecules and.
