What is from the majority of the plasma membrane of cells ?

Phospholipids

Explanation:

Cell membrane is an important type of cellular structure in the cells of living organisms. It functions to allow selective movement of materials or substances in an out of the cell.

Cell membrane is made up of a phospholipid bilayer and proteins embedded in it. Phospholipids form this lipid bilayer which is the basic structure of the cell membrane. The membrane also contains cholesterol molecules which help in keeping the membrane fluid consistent.

Additionally, the membrane also contains proteins whose function is to enhance the transportation of materials across the membrane.

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