A phospholipid is a lipid that contains a phosphate group as part of its structure.

Many consist of a glycerol backbone with three fatty acids attached.

A phospholipid consists of a glycerol backbone with two fatty acids, a phosphate group, and a polar molecule.

The phosphate group and polar molecule form the hydrophilic head of the lipid, while the fatty acids form a hydrophobic tail.

When phospholipids are placed in water, they orient themselves into a bilayer.

The non-polar tails are on the inside of the bilayer, while the polar heads are on the outside and face the water.

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Phospholipids are a major component of cell membranes.