Where in the cell do you find lipids?

Cell membranes have lipids, in fact, it contains almost a billion lipid molecules. These lipid molecules constitute almost half the mass of cell membrane. These membranes are made up of phospholipid bilayers. These lipid molecules are amphipathic, that is, they contain both a hydrophobic end and a hydrophilic end. The phospholipid molecule contains the hydrophilic head and two hydrophobic tails. This unique structure enables these molecules to instantly form bilayers. The cell membrane acts as a selectively permeable barrier between the cell interior and the outside environment. Only certain select molecules can pass into the cell, either through active or passive transport; the rest are unable to enter the cell. Waste molecules generated during cell operations are also excreted through the membrane, thereby maintaining cell homeostasis. 

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