EVERYDAY SCIENCE

Detailed explanation-1: -Unsaturated fatty acids have at least one double bond, creating a “kink” in the chain. The double bond increases fluidity. Membrane fluidity is also affected by cholesterol. Cholesterol can make the cell membrane fluid as well as rigid.

Detailed explanation-2: -It was found that the saturated fatty acid makes the model membrane more rigid, while the presence of unsaturated fatty acid increases its fluidity. The increasing amount of stearic acid gradually destabilizes model membrane, however, this effect is the weakest at low content of SFA in the mixed monolayer.

Detailed explanation-3: -If unsaturated fatty acids are compressed, the “kinks” in their tails push adjacent phospholipid molecules away, which helps maintain fluidity in the membrane.

Detailed explanation-4: -At higher temperatures, phospholipids have enough kinetic energy to overcome the intermolecular forces holding the membrane together, which increases membrane fluidity.

Detailed explanation-5: -8 Increasing cis-unsaturated fatty acyl composition increases membrane fluidity (or decreases microviscosity and order), while increasing the saturated or trans-unsaturated fatty acyl composition decreases membrane fluidity.