Biochemistry for Medical Laboratory Science – Carbohydrate Chemistry (Part 1)

Vocabulary flashcards cover fundamental terms, structures, stereochemistry and biological roles of carbohydrates discussed in the lecture notes.

Carbohydrate

Polyhydroxy aldehyde or ketone composed of carbon, hydrogen and oxygen; primary energy source for the body.

Carbonyl Group

A carbon atom double-bonded to oxygen (C=O); determines whether a sugar is an aldose or ketose.

Sugar (biochemical)

General term for monosaccharides and some oligosaccharides.

Monosaccharide

Single-unit sugar (e.g., glucose).

Oligosaccharide

Short chain of 2–10 monosaccharide units (e.g., disaccharides).

Polysaccharide

Carbohydrate with >10 monosaccharide units (e.g., cellulose).

Aldose

Sugar whose carbonyl group is at C1, forming an aldehyde.

Ketose

Sugar whose carbonyl group is at C2, forming a ketone.

Polyhydroxy Aldehyde

Aldose containing multiple hydroxyl (–OH) groups.

Polyhydroxy Ketone

Ketose containing multiple hydroxyl (–OH) groups.

Fischer Projection

Straight-chain drawing with carbon chain vertical; shows D/L configuration.

Haworth Projection

Planar ring diagram of sugars; thick bond nearer the viewer.

Furanose Ring

Five-membered sugar ring (4 C + 1 O).

Pyranose Ring

Six-membered sugar ring (5 C + 1 O); 99 % of glucose exists in this form.

Anomeric Carbon

Former carbonyl carbon that becomes chiral in the ring; site for α/β distinction.

Penultimate Carbon

Highest-numbered chiral carbon; its –OH orientation defines D or L form.

Chiral (Asymmetric) Carbon

Carbon attached to four different groups, allowing stereoisomerism.

D-Configuration

Penultimate –OH projects right in Fischer; last carbon up in chair form.

L-Configuration

Penultimate –OH projects left in Fischer; last carbon down in chair form.

α-Anomer

–OH on anomeric carbon opposite the penultimate carbon’s projection.

β-Anomer

–OH on anomeric carbon on the same side as the penultimate carbon; 62 % of glucose.

Isomer

Compounds with identical formula but different spatial arrangement.

Enantiomer

Non-superimposable mirror-image isomers (D vs L).

Epimer

Stereoisomers differing at only one chiral carbon (e.g., glucose vs galactose at C4).

Newman/Chair Conformation

Three-dimensional depiction showing actual spatial shape of sugar rings in solution.

Energy Yield of Carbohydrates

Oxidation of 1 g carbohydrate produces ~4 kcal (17 kJ).

Deoxyribose

Pentose sugar component of DNA.

Ribose

Pentose sugar component of RNA.

Glycoprotein

Protein covalently bonded to carbohydrate; includes transporters like transferrin and ceruloplasmin.

Type A Blood Sugar

Terminal sugar N-acetyl-D-galactosamine (GalNAc) on red-cell surface glycoproteins.

Type B Blood Sugar

Terminal sugar D-galactose on red-cell surface glycoproteins.

Type AB Blood

Both GalNAc and D-galactose terminal sugars present.

Type O Blood

Lacks both GalNAc and D-galactose terminal sugars.