Insulators nonpolar lipids

Lipids are chemical components of the cell that are insoluble in water but soluble in nonpolar solvents. Lipids include fatty acids, fats, oils, phospholipids, glyco-lipids, and steroids. Insolubility in water makes lipids an ideal structural component of cell membranes. Lipids make up the containers that separate the interior of the cell from its external environment. Lipids are also used for long-term energy storage and for insulation. We all store extra calories from food as lipids, some of us more than others. 

Lipids are biological chemicals that are nonpolar and, therefore, insoluble in water. In our bodies, they compose cell membranes, store energy, and provide insulation. 

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