Biological Molecules: Lipids

These flashcards cover key concepts related to lipids, including their types, structures, and functions based on the provided lecture notes.

Triglycerides

A type of lipid formed from one glycerol molecule and three fatty acids.

Phospholipids

A type of lipid where one fatty acid of triglyceride is substituted by a phosphate-containing group.

Saturated fatty acid

A fatty acid with no C=C double bonds in its hydrocarbon chain, where all carbons are fully saturated with hydrogen.

Unsaturated fatty acid

A fatty acid that contains one or more C=C double bonds in the hydrocarbon chain, introducing bends or kinks.

Fatty Acid Structure

Composed of a variable R-group (hydrocarbon chain) and a carboxyl group (-COOH).

Ester bonds

Bonds formed during the formation of triglycerides, linking glycerol and fatty acids.

Hydrophobic

Property of molecules, like triglycerides, that causes them to be insoluble in water.

Hydrophilic

Property of phosphate heads in phospholipids, making them attracted to water.

Bilayer

A structure formed by phospholipids in cell membranes, allowing selective permeability.

Test for lipids

Add ethanol to dissolve lipids, then add water; a positive result shows a milky white emulsion.