Lipids and Their Role in Biological Systems

A set of flashcards covering key terms and definitions related to lipids, their structures, types, functions, and their biological significance.

Lipids

Biomolecules that contain fatty acids or a steroid nucleus, are soluble in organic solvents but not in water.

Fatty Acids

Long, unbranched carbon chains with a carboxylic acid group, typically 12-18 carbon atoms long.

Saturated Fatty Acids

Fatty acids containing only single carbon-carbon bonds.

Unsaturated Fatty Acids

Fatty acids that contain one or more double carbon-carbon bonds.

Monounsaturated Fatty Acids

Fatty acids with only one double bond in the carbon chain.

Polyunsaturated Fatty Acids

Fatty acids with two or more double bonds in the carbon chain.

Essential Fatty Acids

Fatty acids that must be obtained from the diet, such as linoleic acid and linolenic acid.

Hydrogenation

The process of adding hydrogen to unsaturated fatty acids to convert double bonds into single bonds.

Trans Fatty Acids

Fatty acids resulting from hydrogenation that behave like saturated fatty acids and are known to raise LDL cholesterol.

Prostaglandins

Hormone-like substances produced from arachidonic acid, functioning in various biological processes.

Phospholipids

Lipids similar to triglycerides but containing a phosphate group, key components of cell membranes.

Lipoproteins

Complexes of lipids and proteins that transport lipids through the bloodstream.

Cholesterol

An important and abundant steroid in the body, necessary for cell membranes and various hormones.

Bile Salts

Synthesized from cholesterol in the liver, aiding in the digestion and absorption of fats.

Cell Membranes

Semipermeable structures composed of lipid bilayers that separate cellular contents from the external environment.

Fluid Mosaic Model

The model describing the cell membrane structure, where proteins and cholesterol are embedded in a lipid bilayer.