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Lipid bilayers formed between two aqueous phases have thisimportant property: they form two-dimensional sheets, the edges ofwhich close upon each other and undergo self-sealing to formliposomes.

a. What are the forces that drive bilayerformation? What are the consequences of this property for thestructure of biological membranes?

b. Explain why phosphoglycerides are capable of spontaneouslyassembling into the bilayer structure found in biological membranesbut triacylglycerols are not.

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Answer:

a-The assembly process is driven by interactions between hydrophobic molecules (also called the hydrophobic effect), an increase in interactions between hydrophobic molecules (which causes clustering of hydrophobic regions) allows water molecules to bond more directly between Yes, the entropy of the system increased. This complex process includes non-covalent interactions, tales like Van der Waals, electrostatic bonding, and hydrogen bonding.

b-The fluidity of the membranes depends mainly on the length and the level of unsaturation of the phospholipids. Indeed, the shorter and more unsaturated the membrane lipids, the more fluid the membrane is. This is due to the fact that long chains show a greater association with each other. Specifically, for each -CH2- group added, the free energy of interaction between two chains decreases by 0.5 kcal mol-1, making the interaction stronger. When the chains are shorter, the interaction between the alkyl groups of the lipids is reduced.

Step-by-step explanation:

The lipid bilayer is a thin polar membrane made up of two layers of lipid molecules, membranes are flat sheets that form a continuous barrier around cells and their structures

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