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 water 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 lipid 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 flipflop Rarely occurs 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
●00 unsaturated saturated straight hydrocarbon 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
H polar head group CH rigid planar steroid ring CH3 CH3 structure clclc nonpolar drocarbon CH hy tail Ha 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)