Biological Macromolecules and Lipids: Carbohydrates

Practice flashcards covering the characteristics, synthesis, and classification of carbohydrates, including monosaccharides, disaccharides, and polysaccharides based on the Campbell Biology text.

Macromolecules

Large and complex biological molecules with unique properties that arise from the orderly arrangement of their atoms.

Polymer

A long molecule consisting of many similar building blocks called monomers.

Monomers

The repeating units that serve as the building blocks for a polymer.

Enzymes

Specialized macromolecules that speed up chemical reactions, such as those that make or break down polymers.

Dehydration reaction

A reaction (also called condensation) that occurs when two monomers bond together through the loss of a water molecule.

Hydrolysis

A chemical reaction that disassembles polymers into monomers by adding a water molecule, essentially the reverse of a dehydration reaction.

Monosaccharides

The simplest carbohydrates or simple sugars, which have molecular formulas that are usually multiples of $CH_2O$.

Glucose

The most common monosaccharide, with the molecular formula $C_6H_{12}O_6$.

Aldose

A classification of monosaccharide known as an aldehyde sugar, based on the location of the carbonyl group.

Ketose

A classification of monosaccharide known as a ketone sugar, based on the location of the carbonyl group.

Trioses

Three-carbon sugars with the molecular formula $C_3H_6O_3$, such as Glyceraldehyde and Dihydroxyacetone.

Pentoses

Five-carbon sugars with the molecular formula $C_5H_{10}O_5$, such as Ribose and Ribulose.

Hexoses

Six-carbon sugars with the molecular formula $C_6H_{12}O_6$, including Glucose, Galactose, and Fructose.

Glycosidic linkage

A covalent bond formed between two monosaccharides by a dehydration reaction.

Maltose

A disaccharide formed by the union of two glucose molecules through a $1-4$ glycosidic linkage.

Sucrose

A disaccharide formed by the union of glucose and fructose through a $1-2$ glycosidic linkage.

Polysaccharides

Polymers of sugars that serve storage and structural roles, determined by their sugar monomers and the positions of their glycosidic linkages.

Starch

A storage polysaccharide of plants consisting entirely of glucose monomers, stored as granules within chloroplasts and other plastids.

Amylose

The simplest, unbranched form of starch.

Amylopectin

A somewhat branched form of starch found in plants.

Glycogen

A branched storage polysaccharide in animals, stored mainly in liver and muscle cells.

Cellulose

A structural polysaccharide that is a major component of the tough wall of plant cells, consisting of $\beta$ glucose monomers in a straight, unbranched configuration.

Microfibrils

Strong building materials for plants formed by parallel cellulose molecules held together by hydrogen bonds between hydroxyl groups.

Insoluble fiber

The term for cellulose in human food as it passes through the digestive tract because human enzymes cannot hydrolyze $\beta$ linkages.

Chitin

A structural polysaccharide found in the exoskeleton of arthropods and the cell walls of many fungi.