Organic Chemistry of Carbohydrates

These flashcards cover key concepts from the lecture on carbohydrates, including structures, classifications, reactions, and properties.

What are carbohydrates classified as chemically?

Carbohydrates are polyhydroxy aldehydes or polyhydroxy ketones.

What is the difference between simple and complex carbohydrates?

Simple carbohydrates are monosaccharides, while complex carbohydrates include disaccharides, oligosaccharides, and polysaccharides.

What is the smallest aldose?

Glyceraldehyde is the smallest aldose.

What distinguishes D-sugars from L-sugars?

An L-sugar is the mirror image of a D-sugar.

What do the terms D and L signify in sugar nomenclature?

D and L indicate the configuration, not the optical activity like (+) and (−).

What are epimers?

Epimers are sugars that differ in configuration at one asymmetric center.

What is the formula for aldoses?

The formula for aldoses is Cn(H2O)n.

What functional group can be oxidized by bromine?

Only aldehydes can be oxidized by bromine.

What is the Kiliani–Fischer synthesis used for?

The Kiliani-Fischer synthesis increases the carbon chain of an aldose by one carbon.

What is the difference between a reducing sugar and a nonreducing sugar?

A reducing sugar has an aldehyde, ketone, or hemiacetal group; a nonreducing sugar does not.

What differentiates amylose from amylopectin?

Amylose has a simple, unbranched structure, while amylopectin is branched.

What defines the structure of glycoproteins?

Glycoproteins are proteins bonded to oligosaccharides.

What is the result of glycosidic bond cleavage in lactose?

Lactase is the enzyme that cleaves the glycosidic bond in lactose.

How do D-ribose and D-2-deoxyribose differ?

D-ribose is the sugar component of RNA, while D-2-deoxyribose is the sugar component of DNA.

What is an amino sugar?

Amino sugars have one or more hydroxyl groups replaced by an amino group.

What sugar is formed from two glucose units?

Maltose is a disaccharide formed from two glucose units.

Which blood type is considered universal donor?

People with type O blood are universal donors.

What is special about the anomeric carbon in sugars?

The anomeric carbon is the first carbon that is connected to two oxygen atoms in cyclic forms.

What geometric forms do hexoses typically adopt?

Hexoses typically adopt either pyranose (six-membered ring) or furanose (five-membered ring) forms.

What is the most stable form of glucose?

Beta-D-glucose is more stable than alpha-D-glucose.