Quiz - Carbohydrates - 1 | Carbohydrates

Organic Chemistry 3 - Quiz - Carbohydrates - 1


What atoms are carbohydrates made of?

A carbohydrate is a biomolecule consisting of carbon, hydrogen and oxygen atoms


What are monosaccharides?

Monosaccharides, also called simple sugars, are the simplest form of sugar and the most basic units of carbohydrates: they are aldehydes (aldoses) or ketones (ketoses) that contain at least 2 additional hydroxy groups. Polysaccharides are polymers of monosaccharides.


What is the most common configuration of sugars in nature?

In nature, the most common configuration of sugars is the D-configuration. This means that the hydroxyl group attached to the chiral carbon farthest from the carbonyl group (C-5 in aldoses and C-4 in ketoses) is on the right side in a Fischer projection.


Which of the following synthesis conditions is used to oxidize sugars to monocarboxylic acid?

Oxidation to mono- or dicarboxylic acids:


What is the mechanism of etherification of sugars?

Ag2O deprotonates each alcohols forming alkoxides RO- which reacts with CH3I in an SN2 reaction


What is the most common monomer of polysaccharides?

Nature is remarkably conservative in the construction of polysaccharides: the 3 most abundant natural polysaccharides (cellulose, starch and glycogen) are derived from the glucose.


How many chirality centers do aldohexoses have?

Aldohexoses have four chirality centers, allowing for a total of 16 possible stereoisomers.


What is the name of a 6-membered ring commonly found in monosaccharides?

A 6-membered ring in monosaccharides is called a pyranose ring, while a 5-membered ring is called a furanose ring.


In which anomeric configuration is the hydroxyl group from the carbonyl carbon cis to the CH2OH group in a cyclic sugar?

In the β-anomer, the hydroxyl group from the carbonyl carbon is cis to the CH2OH group.


What term describes the process by which α- and β-anomers interconvert through an open-chain form?

Mutarotation is the process by which α- and β-anomers interconvert in solution through an open-chain form.