Phospholipid definition, any of a group of fatty compounds, as lecithin, composed of phosphoric esters, and occurring in living cells. Phosphatidylcholine (PC) is a phospholipid attached to a choline particle. Phospholipid bilayer definition, a two-layered arrangement of phosphate and lipid molecules that form a cell membrane, the hydrophobic lipid ends facing inward and the hydrophilic phosphate ends facing outward. Phospholipid Structure. This slight difference in structure gives phospholipids one molecule that repels water and one molecule that attracts water. Phospholipid regulatory functions are both direct and indirect, through their metabolites. A phospholipid is an amphipathic molecule which means it has both a hydrophobic and a hydrophilic component. phospholipid A polar lipid that is a lipid derivative of glycerol which contains one or more phosphate groups. Phospholipids have a similar overall structure to triacylglycerols, but phospholipids have a phosphorus molecule in a location where a fatty acid molecule occurs in triacylglycerols. See more. The phosphorous part of the phospholipid … In this, the two fatty acids would represent the “hydrophobic tails”, while the phosphate group representing the “hydrophilic head”. When structurally seen, a phospholipid is found to be consisting of two fatty acids along with a phosphate group. Phospholipid Structure. It is well established that phospholipids participate in a broad range of cellular events such as apoptosis and regulation of mitochondrial physiology and that phospholipid-derived messenger molecules are crucial for the transduction of extracellular signals to intracellular events. A phospholipid is a type of lipid that is an essential component of many biological membranes, particularly the lipid bilayer of cells. The ‘tail’ is usually made up of two long fatty acid chains. B vitamins, such as inositol and choline, amino acids from proteins and essential fatty acids are all needed for phospholipid production. Phospholipids contain fatty acids, glycerol, and phosphorous. This is because phospholipids are amphipathic compounds in a way that the ‘head’ is hydrophilic and the lipophilic ‘tail’ is hydrophobic. See more. A single phospholipid molecule has a phosphate group on one end, called the “head,” and two side-by-side chains of fatty acids that make up the lipid “tails. Phospholipid synthesis is accomplished within your cells from simpler precursors that are derived from your diet. Phospholipids are particularly important with regard to the structure and functioning of biological membranes because of their amphipathic qualities. A well-balanced diet is the best way to ensure adequate nutrients for phospholipid synthesis.