Chapter 5-An Introduction to Carbohydrates
-The presence of a carbonyl group (C=O) along with multiple hydroxyl groups provides an array of
functional groups in sugars.
-Number of carbon atoms present also varies in monosaccharides.
-Monosaccharides can vary in the spatial arrangement of their atoms.
-Many distinct monosaccharides exist because so many aspects of their structure are variable; alternative
ring forms, optical isomers with different arrangements of hydroxyl groyps in space and different mirror-
image forms, variation in carbon number, and aldose or ketose placement of the carbonyl group. Each has
unique structure and function.
-Simple sugars polymerize when a condensation reaction occurs between two hydroxyl groups, resulting
in a covalent bond called a glycosidic linkage. Location and geometry of glycosidic linkages can vary
-Structural polysaccharides usually exist as sets of long, parallel strands that are linked to each other.
This design gives materials that are made of these molecules the ability to withstand forces that pull or
push on them—what an engineer would call tension and compression. In this way, the structure and
function of structural polysaccharides are correlated.
Functions of carbs:
1. Carbohydrates as structural molecules- cellulose (cell wall), chitin (structural support in
cell walls of fungi and external skeletons of insects and crustaceans), peptidoglycan
(structural support in bacterial cell walls). Form long strands and bonds that can form
between adjacent strands.