Figure 10-4. Liposomes (A)An electron 100nm micrograph of unfixed, unstained water phospholipid vesicles (liposomes)in water The bilayer structure of the vesicles is readily apparent. (B)a drawing of a smal ater spherical liposome seen in cross-Section Liposomes are commonly used as model membranes in experimental studies. (A, courtesy of Jean Lepault 25 nm
Figure 10-4. Liposomes. (A) An electron micrograph of unfixed, unstained phospholipid vesicles (liposomes) in water. The bilayer structure of the vesicles is readily apparent. (B) A drawing of a small spherical liposome seen in cross-section. Liposomes are commonly used as model membranes in experimental studies. (A, courtesy of Jean Lepault.)
water water id bilayer (black membrane Figure 10-5. A cross-sectional view of a synthetic lipid bilayer, called a black membrane. This planar bilayer is formed across a small hole in a partition separating two aqueous compartments. Black membranes are used to measure the permeability properties of synthetic membranes
Figure 10-5. A cross-sectional view of a synthetic lipid bilayer, called a black membrane. This planar bilayer is formed across a small hole in a partition separating two aqueous compartments. Black membranes are used to measure the permeability properties of synthetic membranes
lateral diffusion ifipflop (rarely occursl flexion rotation Figure 10-6. Phospholipid mobility. The types of movement possible for phospholipid molecules in a lipid bilayer
Figure 10-6. Phospholipid mobility. The types of movement possible for phospholipid molecules in a lipid bilayer
●●●● unsaturated saturated straight ydrocarbon chains hydrocarbon chains with cis-double bonds Figure 10-7. Influence of cis-double bonds in hydrocarbon chains. The double bonds make it more difficult to pack the chains together and therefore make the lipid bilayer more difficult to freeze
Figure 10-7. Influence of cis-double bonds in hydrocarbon chains. The double bonds make it more difficult to pack the chains together and therefore make the lipid bilayer more difficult to freeze
OH polar head group CH igid planar steroid ring CH, CH 43 Structure CH CH nonpolar hydrocarbon CH tail CH3 CH3 Figure 10-8. The structure of cholesterol. Cholesterol is represented by a formula in(a), by a schematic drawing in(b), and as a space-filling model in(C)
Figure 10-8. The structure of cholesterol. Cholesterol is represented by a formula in (A), by a schematic drawing in (B), and as a space-filling model in (C)