Carbohydrates

Carbohydrate chemical formula

(CH2O)n

Letter indication of carbohydrates

often indicated w/ “-ose”

Carbohydrate functions

cellular fuel, stored fuel, structural signaling

Carbohydrate Subunit

monosaccharides/sugar

Aldoses

sugar with carbonyl on Carbon 1 (exterior)

Ketoses

sugar with carbonyl on Carbon 2 (interior)

Isomer

internal carbons w/ hydroxyl groups are “chiral”

Biological sugar form

typically D-form

D vs. L Isomers

determined by last chiral carbon

Cyclic Ring Form

predominates in biological forms

Hydroxyl placement on cyclic form

on last carbon or 2nd to last carbon in chain

α - form of glucose

hydroxyl (-OH) on carbon 1 is on same side of C2

β - form of glucose

hydroxyl (-OH) on carbon 1 is on opposite side of C2

Polysaccharides

many glucose held together w/ glycosidic linkage

glycosidic linkage

hydroxyl (-OH) on C1 of glucose forms a glycosidic bond w/ carbon of another glucose; H20 Created

Carbons that the glycosidic linkage is created on

1, 4

Starch

glucose storage polymer in plants

glycogen

glucose storage for fuel (polymer) in animals

Cellulose

part of plant cell wall