Biochemistry – Carbohydrates Vocabulary

Vocabulary flashcards covering key terms and definitions related to carbohydrate chemistry, structure, types, and biological roles.

Monomer

A small molecular building block that joins with others to form larger biomolecules.

Carbohydrate

Polyhydroxy aldehyde or ketone whose empirical formula is (CH2O)n; commonly called “hydrates of carbon.”

Monosaccharide

Simple sugar composed of a single aldehyde or ketone unit; the monomer of carbohydrates.

Aldose

A monosaccharide that contains an aldehyde functional group (R-CHO).

Ketose

A monosaccharide that contains a ketone functional group (RC(=O)R′).

Triose

Three-carbon monosaccharide, e.g., glyceraldehyde or dihydroxyacetone.

Tetrose

Four-carbon monosaccharide; exists as aldotetroses or ketotetroses.

Pentose

Five-carbon monosaccharide; subdivided into aldopentoses (e.g., ribose) and ketopentoses (e.g., ribulose).

Hexose

Six-carbon monosaccharide such as glucose, fructose, or galactose.

Glucose

Primary energy-providing hexose that can cross the blood-brain barrier.

Fructose

‘Fruit sugar’; a ketohexose abundant in honey, fruits, and vegetables.

Galactose

Hexose commonly called ‘milk sugar’; component of lactose.

Disaccharide

Carbohydrate formed when two monosaccharides join via a dehydration reaction.

Glycosidic Bond

Covalent linkage that joins one carbohydrate to another molecule via hydroxyl groups.

Sucrose

Table sugar; disaccharide of glucose + fructose linked α1→β2.

Lactose

Milk sugar; disaccharide of galactose + glucose linked β1→4.

Maltose

Malt sugar; disaccharide of glucose + glucose linked α1→4.

Trehalose

Naturally occurring α-linked glucose disaccharide noted for high water-retention capacity.

Cellobiose

β1→4 linked glucose disaccharide produced from cellulose hydrolysis.

Polysaccharide

Carbohydrate polymer containing more than ~20 monosaccharide units.

Homopolysaccharide

Polysaccharide composed of only one type of monosaccharide monomer.

Heteropolysaccharide

Polysaccharide made of more than one kind of monosaccharide monomer.

Starch

Plant storage polysaccharide consisting of amylose and amylopectin.

Amylose

Unbranched starch component with α1→4 glucose linkages; poorly water-soluble.

Amylopectin

Branched starch component with α1→4 chains and α1→6 branch points; more soluble.

Dietary Fiber

Carbohydrate that resists digestion by human enzymes, aiding glucose regulation and gut health.

Glycogen

Highly branched glucose storage polysaccharide in animals, stored in liver and muscle.

Glycogenolysis

Process of breaking down glycogen to release glucose when blood sugar drops.

Cellulose

β1→4 linked glucose polymer forming plant cell walls; most abundant natural biopolymer.

Chitin

Structural polysaccharide in insect exoskeletons composed of N-acetylglucosamine units.

ATP (in carbohydrate context)

Energy molecule produced when cells oxidize carbohydrates during cellular respiration.