Lipids that are not essential in the diet but are used in the structure of every cell membrane are

Lipid that are not essential in the diet but are used in the structure of every cell membrane is Sphingolipid

Explanation:

Plasma contain various lipids such as phospholipid,glycolipid,cholesterol and Sphingolipid. Among them Sphingolipid is not essential in the diet.

                 But this sphingolipid is very much essential to build the structure of plasma membrane.Sphingolipid is basically composed of aliphatic amino alcohol sphingosine. The basic structure of sphingolipid is built by ceramide .When sphingolipid interract with various sugar molecules such as glucose then the whole complex structure is called cerebroside .

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