Carbohydrates and Structural Polysaccharides

A comprehensive set of vocabulary flashcards covering the definition, classification, chemical structure, and biological functions of carbohydrates, including monosaccharides, disaccharides, and polysaccharides.

Carbohydrate

An organic molecule made of Carbon, hydrogen, and oxygen ($C$, $H$, $O$).

General Formula of Simple Carbohydrates

Follows a $1:2:1$ ratio ($C:H:O$); written as $(CH_2O)_n$, where $n$ is the number of carbons.

Monosaccharide

A single sugar unit and the simplest carbohydrate; examples include Glucose, Fructose, and Galactose.

Glucose

A hexose monosaccharide that serves as the main cellular fuel.

Hexose

A 6-carbon sugar with the chemical formula $C_6H_{12}O_6$.

Isomers

Molecules that share the same chemical formula (such as $C_6H_{12}O_6$) but differ in their structural arrangement.

Aldoses

Monosaccharides containing an aldehyde group, such as Glucose and Galactose.

Ketose

A monosaccharide containing a ketone group, such as Fructose.

Disaccharide

A carbohydrate made of two monosaccharides linked together.

Sucrose

A disaccharide composed of $Glucose + Fructose$.

Lactose

A disaccharide composed of $Glucose + Galactose$.

Maltose

A disaccharide composed of $Glucose + Glucose$.

Glycosidic bond

A covalent bond linking two sugar molecules (a $C-O-C$ bridge) formed by a dehydration reaction.

Dehydration (condensation) reaction

A reaction that joins two monosaccharides by removing water to form a new bond.

Polysaccharide

A polymer consisting of many monosaccharides linked by glycosidic bonds.

Storage polysaccharides

Polymers that store energy as long chains of glucose, such as Starch in plants and Glycogen in animals.

Structural polysaccharides

Polymers that provide strength and support to cells and tissues, such as Cellulose and Chitin.

Starch

A plant storage polysaccharide of alpha-glucose units stored in plastids (amyloplasts); exists as amylose and amylopectin.

Glycogen

A highly branched animal storage polysaccharide of alpha-glucose stored mainly in the liver and skeletal muscle.

Cellulose

A structural polysaccharide in plant cell walls made of beta-glucose units in straight chains that form strong fibers via hydrogen bonding.

Chitin

A structural polysaccharide found in fungal cell walls and arthropod exoskeletons; it is similar to cellulose but contains nitrogen-containing groups.

Alpha-glucose

An anomer where the $OH$ group on the first carbon ($C1$) is on the opposite side of the ring as the $CH_2OH$ group.

Beta-glucose

An anomer where the $OH$ group on the first carbon ($C1$) is on the same side of the ring as the $CH_2OH$ group.

Hydrolysis

A reaction that breaks disaccharides or polysaccharides into smaller sugars by adding water to break the glycosidic bond.

Pentose sugar

A 5-carbon sugar; examples include Ribose (found in RNA and $ATP$) and Deoxyribose (found in DNA).