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2.6. Carbohydrates. 2.6. Carbohydrates. Carbohydrates are made from CARBON, HYDROGEN and OXYGEN. They STORE ENERGY in plants and animals. Plant cell walls depend on the structural role of some carbohydrates. CARBOHYDRATES. MONOSACCHARIDES. DISACCHARIDES. POLYSACCHARIDES.
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2.6 Carbohydrates 2.6
Carbohydrates Carbohydrates are made from CARBON, HYDROGEN and OXYGEN They STORE ENERGY in plants and animals Plant cell walls depend on the structural role of some carbohydrates CARBOHYDRATES MONOSACCHARIDES DISACCHARIDES POLYSACCHARIDES
Number of Carbon atoms Monosaccharides Monosaccharides are small organic molecules used as bulding blocks for more complex carbohydrates. Click each of the blue boxes to work through the slide. What does the ‘n’ stand for? General Formula (CH2O)n TRIOSE, e.g. glyceraldehyde - In metabolic reactions So, when n=3 When n=5 When n=6 PENTOSE, e.g. ribose – formation of nucleic acid HEXOSE, e.g. glucose - main source of energy next
Oxygen Hydrogen Carbon Hydroxide (OH) CH2OH CH2OH Isomerism in Glucose C6H12O6 Alpha-glucose beta-glucose Show structural change
WATER WATER WATER Disaccharides Disaccharides form when two monosaccharide units join forming a glycosidic bond, by a condensation reaction. A disaccharide can be made from two of the same monosaccharide molecule or from two different ones. The combination of monosaccharides determines which disaccharide is formed. MONOSACCHARIDES DISACCHARIDE GLUCOSE GLUCOSE GLUCOSE SUCROSE MALTOSE LACTOSE FRUCTOSE GALACTOSE GLUCOSE
CH2OH CH2OH CH2OH H H H H H H OH OH H H OH OH OH OH OH OH H H CH2OH CH2OH C C C C O O O O C C C C C C C C H H H H H H C C C C C C C C OH OH H H OH OH OH OH OH OH H H O O Glycosidic Bond H H Forming Disaccharides Glucose Maltose This is a CONDENSATION reaction, where a water molecule is lost.
1-6 GLYCOGEN Polysaccharides Polysaccharides are large complex molecules known as POLYMERS. What is a monomer? What is polymerisation ? Click the bubble for the answer Polymerisation is the process of bonding many MONOMERS by condensation reactions to form one large molecule. Monomers are the individual monosaccharides which join to form the polysaccharide. Monomer Glycosidic bond α Glucose STARCH 1-4 β Glucose 1-4 CELLULOSE Polysaccharides α Glucose Next Return to isomerism of glucose
C C C C O O O O C C C C C C C C C C C C C C C C OH OH OH OH OH OH O O O O O O H H H H H H Forming polysaccharides Glucose CH2OH CH2OH CH2OH CH2OH H H H H H H H H H H H H OH OH OH OH H H H H OH OH OH OH OH OH H H H H In this example, 3 condensation reactions have produced 3 water molecules to produce the polysaccharide. A HYDROLYSIS reaction (addition of water) reverses the reaction and splits the polysaccharide releasing 3 monosaccharide molecules.
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