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Carbohydrates. http://www.youtube.com/watch?v=_ qf_r5EVP6U. Carbohydrates. Contain hydroxyl groups and one aldehyde or ketone General molecular formula (CH 2 O) n Contains C,H and O in a 1:2:1 proportion. Monosaccharides.
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Carbohydrates http://www.youtube.com/watch?v=_qf_r5EVP6U
Carbohydrates • Contain hydroxyl groups and one aldehyde or ketone • General molecular formula (CH2O)n • Contains C,H and O in a 1:2:1 proportion
Monosaccharides • http://ferraribiblog.wordpress.com/2012/10/05/dna-and-rna-so-tiny-so-great/ • http://eureka.mpronovost.ep.profweb.qc.ca/index.php/Question_16_:_Pourquoi_les_appelle-t-on_des_hexoses%3F • The monomer unit of polysaccharides • Pentoses – 5 carbon with 5 functional groups (4 –OH + 1 aldehyde or ketone) • Hexoses – 6 carbon with 6 functional groups (5 – OH + 1 aldehyde or ketone)
Monosaccharides[con’t] • Both form ring structures in water as OH reacts with another functional group
Glucose – A pivotal molecule • http://en.wikipedia.org/wiki/Anomer • Important in cellular respiration and photosynthesis • Good energy storage molecule (polymerizes and depolymerizes easily) • Important in the synthesis of other biomolecules
Disaccharides • Glycosidic linkages form between 2 monosaccharides • Usually formed between carbon 1 of one monomer and carbon 4 or 6 of the other • Disaccharides formed via a condensation reaction and broken down by a hydrolysis reaction
Polysaccharides • Long chains of α 1-4 or α 1-6 glycosidic linked sugars • May/may not be branched • A few 100 to a few thousand monosaccharideslong • Increased # branches causes increased insolubility
Storage polysaccharides • Amylose – long chain α 1 – 4 glucose • Amylopectin - long chain α1 – 4 glucoses with highly branched 1 – 6 linkages (1 every 20 – 25 glucose) • Animal Glycogen – more highly branched than amylopectin (1 every 6 – 10 glucose) • Stored mainly in the liver and muscle cells - More water soluble than plant starch Plant Starch Animal ‘Starch’
Structural polysaccharides • Most abundant component of plant cell wall • Composed of β-glucose • Long chain of β 1-4 linkages • Humans cannot digest • A modified glucose • A component in insect exoskeletons • A component in fungal cell walls • Composed of the monomer unit glucosamine Cellulose Chitin