1.2 Biologically Important Molecules (Carbohydrates)

Macromolecule

A large complex molecule (polymer) made of many smaller structural units (monomers) covalently linked together.

Monomer

A small molecule; the building blocks of polymers.

Polymer

A long-chain molecule made up of a repeated pattern of monomers.

Condensation/Dehydration Synthesis Reaction

An anabolic reaction where large molecules are built from small subunits, requiring energy and releasing water.

Hydrolysis Reaction

A catabolic reaction where large molecules are broken down into small subunits, using water and releasing energy.

Carbohydrates

Biologically important molecules that are used as a source of energy and/or structural support, containing C, H, O in a 1:2:1 ratio.

Monosaccharide

The simplest form of carbohydrates, composed of 3 to 7 carbon atoms; examples include glucose, galactose, and fructose.

Disaccharide

A carbohydrate composed of two monosaccharides joined through a condensation reaction.

Polysaccharide

A carbohydrate that contains ten to hundreds of monosaccharides linked together.

Glycosidic Linkage

The covalent bond formed between two monosaccharides during a condensation reaction.

Starch

A polysaccharide that serves as glucose storage in plants.

Glycogen

A polysaccharide that serves as glucose storage in animals, found in the liver and skeletal muscles.

Cellulose

A structural polysaccharide in plant cell walls, composed of β 1-4 glycosidic linkages.

Chitin

A structural polysaccharide that forms the exoskeleton of arthropods and is also found in fungi.

Dietary Fiber

Group of plant polysaccharides that cannot be digested by humans due to lack of enzymes to break down glycosidic linkages.