Download Carbohydrates

Chapter 22
General Information
 General Formula Cx(H2O)y
 Sugars or saccharides ending (OSE)
 Defined as polyhydroxy aldehydes (aldoses) and
ketones (ketoses) or substances that hydrolyze to yield
polyhydroxy aldehydes and ketones.
 Most abundant organic constituents of plants
 Major source of “quick” energy ~4 Kcal/g
 Support tissue
Monosaccharides
 One unit of sugar
 Simple sugar
 Classification
 Either contain and aldehyde (Aldose) or ketone (Ketose)
 Number of Carbons (Triose, Tetrose, Pentose, Hexose
 Pyran (6 membered ring) or Furan (5 membered ring)
 Main biological monosaccharaides
 Glucose
 Fructose
 Galatose
 Ribose
Reducing Sugars
 Test positive with Tollens’ or Benedict’s solutions
 Undergo Oxidations
 All carbohydrates that contain a hemiacetal group
 Equilibrium with aldehydes or α–hydroxy ketones
Disaccharides
 Two monomers connected via a condensation reaction
 Common biological disaccharides
 Maltose (Wheat sugar–malt, glucose–glucose, α-1,4
glycosidic bonds, reducing sugar )
Maltose (α-1,4)
Cellobiose (β-1,4)
Disaccharides
 Common biological disaccharides continued
 Sucrose (Table sugar, glucose–fructose, nonreducing
sugar, most widely occurring disaccharide, α1-β2
glycosidic bond
Disaccharides
 Common biological disaccharides continued
 Lactose (Milk sugar, galactose–glucose, reducing sugar,
β-1,4 glycosidic bond)
Polysaccharides
 Oligo (Few 2 to 10) Poly (Many greater that 10)
 Starch
 Amylose
 Amylopectin
 Glycogen
 Cellulose
Other Biologically Important Sugars
 Glycosylamines
 A sugar in which an amino group replaces the anomeric
hydroxy group.
 Nucleoside
Other Biologically Important Sugars
 Amino Sugars
 A sugar in which an amino replaces a nonanomeric
hydroxy group
 Chitin
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Contains D-Glucosamine
Shells of lobsters and crabs
Exoskeleton of insects and spiders
Heparin – prevents clot formation
Other Biologically Important Sugars
 Glycolipids and Glycoproteins
 Glycocalyx
 Cell recognition
 Immune system
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Healing
Autoimmune diseases
Cancer
Blood Groups
Other Biologically Important Sugars
 Glycolipids and Glycoproteins
 Glycocalyx
 Cell recognition
 Immune system
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
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Healing
Autoimmune diseases
Cancer
Blood Groups
Organic Reactions