Lipids and Their Functions

These flashcards cover essential vocabulary related to lipids, their classes, structures, properties, and biological functions.

Triacylglycerols

Energy storage molecules that provide thermal insulation.

Waxes

Long chain fatty acid esters that keep skin lubricated and waterproof.

Phospholipids

Amphipathic molecules that are major components of cell membranes.

Sphingolipids

Lipid components of membranes, particularly in nervous tissue.

Sterols

Precursors of important biological compounds including hormones and vitamin D.

Fatty acids

Molecules composed of hydrocarbon chains with a polar carboxyl group.

Amphipathic molecules

Molecules that contain both hydrophilic and hydrophobic regions.

Unsaturated fatty acids

Fatty acids that contain one or more double bonds in their hydrocarbon chains.

Saturated fatty acids

Fatty acids that do not contain double bonds in their hydrocarbon chains.

Hydrophilic

Having an affinity for water; water-loving.

Hydrophobic

Repelling water; water-fearing.

Melting point

The temperature at which a fatty acid changes from solid to liquid.

Emulsification

The process by which fatty acids disperse oils into finer droplets.

Hydrogenation

The chemical process of adding hydrogen to unsaturated fats to saturate them.

Rancidity

Degradation of fats leading to unpleasant tastes and odors.

Essential fatty acids

Fatty acids that must be obtained from diet because the body cannot synthesize them.

Phosphatidyl choline (lecithin)

A phospholipid involved in cell membrane structure and function.

Sphingomyelins

Class of sphingolipids important for the structure of cell membranes.

Steroids

Lipid molecules characterized by a structure of four fused carbon rings.

Cholesterol

A major sterol in animal tissues that serves as a precursor for many compounds.