Carbohydrates and Lipids Definitions

Carbohydrates Definitions

• Monosaccharide: Single sugar unit; simplest form of carbohydrates.
• Disaccharide: Composed of two monosaccharide units.
• Oligosaccharide: Contains 3-10 monosaccharide units.
• Polysaccharide: Made up of more than 10 monosaccharide units.
• Aldose: Carbohydrate with an aldehyde group as its carbonyl functional group.
• Ketose: Carbohydrate with a ketone group as its carbonyl functional group.
• Triose: A carbohydrate with three carbon atoms; prefixes indicate the number of carbons (tri- to hept-).

Lipids Definitions

• Lipid: Hydrophobic biological molecule; insoluble in water.
• Fatty Acid: A long hydrocarbon chain carboxylic acid.
• Amphiphilic/Amphipathic: Molecules that possess both hydrophilic (water-attracting) and hydrophobic (water-repelling) properties.
• Saturated Fatty Acid: Fully reduced fatty acid with no double or triple bonds.
• Unsaturated Fatty Acid: Contains one or more double bonds in the carbon chain.

Saturated Fatty Acids Structures

• Lauric Acid (12:0): Dodecanoic acid; structure: CH3(CH2)10COOH.
• Myristic Acid (14:0): Tetradecanoic acid; structure: CH3(CH2)12COOH.
• Palmitic Acid (16:0): Hexadecanoic acid; structure: CH3(CH2)14COOH.
• Stearic Acid (18:0): Octadecanoic acid; structure: CH3(CH2)16COOH.
• Arachidic Acid (20:0): Eicosanoic acid; structure: CH3(CH2)18COOH.

Unsaturated Fatty Acids Structures

• Palmitoleic Acid (16:1n-7): 9-Hexadecenoic acid; structure: CH3(CH2)5CH=CH(CH2)7COOH.
• Oleic Acid (18:1n-9): 9-Octadecenoic acid; structure: CH3(CH2)7CH=CH(CH2)7COOH.
• Linoleic Acid (18:2n-6): 9,12-Octadecadienoic acid; structure: CH3(CH2)4(CH=CHCH2)2(CH2)6COOH.
• α-Linolenic Acid (18:3n-3): 9,12,15-Octadecatrienoic acid; structure: CH3CH2(CH=CHCH2)3(CH2)6COOH.
• Arachidonic Acid (20:4n-6): 5,8,11,14-Eicosatetraenoic acid; structure: CH3(CH2)4(CH=CHCH2)4(CH2)2COOH.
• EPA (20:5n-3): 5,8,11,14,17-Eicosapentaenoic acid; structure: CH3CH2(CH=CHCH2)5(CH2)2COOH.
• DHA (22:6n-3): 4,7,10,13,16,19-Docosohexenoic acid; structure: CH3CH2(CH=CHCH2)6CH2COOH.

Carbohydrates Structures

• Glyceraldehyde: A triose carbohydrate, with an aldehyde group.
• Glycerol: A simple polyol compound; backbone for lipids.
• Ethanolamine: Amino alcohol; building block for phospholipids.
• Choline: Nutrient; precursor for acetylcholine and phospholipids.
• Glucose: A primary energy source for cells; a hexose sugar.
• Galactose: A component of lactose; hexose sugar.
• Fructose: A sugar found in many plants; often referred to as fruit sugar.