Lipid: Quick Facts

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Oct. 14, 2026

Facts

Also Known As	oil

Photos and Videos

A composite diagram shows the structural formulas, space-filling models, and simplified depictions of lipid molecules including stearic acid and phosphatidylcholine, and how these assemble into a micelle and lipid bilayer, with labels identifying hydrophilic heads and hydrophobic tails.

False color TEM micrograph of an oogonium with a green nucleus outlined in pink, dark blue nucleolus, light blue cytoplasm, red mitochondria, and yellow lipid droplets.

Diagram showing the structural formula of stearic acid, a lipid, with a carboxyl group at one end and a long hydrocarbon chain labeled along the molecule.

Structural formula diagram of oleic acid, a lipid molecule, showing a long hydrocarbon chain with a single double bond and a carboxyl group at one end.

Diagram showing a single fatty acid molecule with a pink hydrophilic head and blue hydrophobic tail, and a spherical micelle formed by many such molecules arranged with heads outward and tails inward.

Structural formula diagram of a tristearin molecule showing a central glycerol backbone highlighted in pink, with three long stearic acid fatty acid chains branching downward, each composed of repeating CH2 units.

Simple diagram of a lipid bilayer showing two layers of phospholipid molecules with round hydrophilic heads facing outward and hydrophobic tails facing inward, illustrating a cellular membrane structure.

Cross-sectional diagram of a liposome, showing concentric bilayers formed by phospholipid molecules with pink heads and blue fatty acid tails, illustrating its structure in biochemistry.

Structural formula diagram of a glycerolphospholipid molecule, showing a glycerol backbone connected to a phosphate group and two long fatty acid chains labeled R1 and R2.

Structural formula diagram of a sphingolipid molecule, highlighting its long fatty acid chain and labeled chemical groups, with the sphingoid base backbone and fatty acid chain sections shaded in different colors.

Diagram of a lipid molecule showing its molecular structure with carbon, hydrogen, and oxygen atoms highlighted against a blue background.

Close-up of yellow oil droplets suspended and separated from water, visually demonstrating the hydrophobic effect and immiscibility of oil and water.

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Topics

proteolipid thromboxane lipopolysaccharide leukotriene glyceride coacervate lipolysis chylomicron Steroid Isoprenoid Protein Hormone carboxylic acid hydrocarbon heterocyclic compound organosulfur compound Nucleic acid Carbohydrate organometallic compound vitamin

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Key People

Pieter Cullis wearing a suit jacket and light blue shirt, smiling at the camera against a neutral background.

Pieter Cullis

Canadian biochemist and physicist