Transition temperature of lipid bilayers of cell membranes is increased by
|B||Saturated fatty acids|
|C||Unsaturated fatty acids|
a. The fluid mosaic model of membrane structure proposed by Singer and Nicholson, is now widely
b. Transition temp. Tm → The temperature at which the structure undergoes from ordered stiff to
disordered fluid, i.e. melt
a. The Longer and more saturated fatty acid chains interacts more strongly with each other via their
Longer Hydrocarbon chains → thus ↑Tm, ↑stiff i.e. higher temperature is required to increase the fluidity of the bilayer.
b. Unsaturated fatty acids: cis configuration →↑fluidity of lipid bilayer i.e↓Tm
d. At temp. below Tm →↑ fluidity
e. At temp. above Tm →↑ limiting the fluidity
f. At high cholesterol: phospholipid ratio →Transition temperature TM are abolished altogether.