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Cell Membranes are Lipid Bilayers
Cell membrane are lipid bilayers. Lipid bilayers are made of phospholipids. Phospholipids contain a phosphate group "head" and lipid "tail." The phosphate group is hydrophilic, or water loving, and the lipid "tail" is hydrophobic. The hydrophilic head faces the aqueous environment inside and outside of the cell and the hydrophobic tails face each other forming a lipid bilayer.
References Heather Newman ScienceMusicsVideos

