Temperature influences the activity of molecules At higher t

Temperature influences the activity of molecules. At higher temperatures molecules are more active while at lower temperatures they are less active. Based on what you know about the properties of unsaturated & saturated lipid tails, which would be more likely to maintain its fluidity at lower temperatures? Why?

Solution

Unsaturated lipid tails are more likely to maintain its fluidity at lower temperatures than saturated ones. Saturated lipid tails are saturated with hydrogen atoms around carbon and do not contain double bonds. This results in a relatively straight tail. At lower temperature, the straight chains are compressed and pressed onto each other to form a rigid membrane. However, unsaturated lipid tails contain one or more cis double bonds between adjacent carbon atoms. Each double bond produces a bend (kink) of approximately 30 degrees in the lipid tail. This kink makes it more difficult to pack together at lower temperature resulting in the unsaturated lipid tail to remain fluid at lower temperature.