The diagram below represents the arrangement of a type of molecule found in the plasma membrane of a cell - VCE - SSCE Biology - Question 2 - 2015 - Paper 1

In the context of the plasma membrane, the structure labelled X typically represents a fatty acid. Fatty acids are key components of phospholipids, which make up the lipid bilayer of the membrane. They consist of long hydrocarbon chains, which interact with the hydrophobic interior of the membrane, while their carboxylic acid group remains exposed to the aqueous environment. This arrangement is crucial for maintaining the structure and function of cell membranes.