A phospholipid has two fatty acids, a glycerol and phosphate. The phosphate head is soluble and hydrophyillic but the fatty acid tails are insoluble and hydrophobic.
Diagram of phospholipid
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Simple structure of phospholipid
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Two layers of phospholipids form a bilayer with the hydrophobic region which are the phospholipid tails pointing inwards and the hydrophillic heads pointing outwards toward the water. This is the basis of the phosopholipid bilayer in the cell surface membrane
