BIO 101 1st Edition Lecture 6 Outline of Last Lecture I Intro to macromolecules II Dehydration Synthesis III Proteins a Amino acids b Polypeptide chains IV Levels of Protein Structure a Primary b Secondary c Tertiary d Quaternary Outline of Current Lecture I Carbohydrates a Monosaccharide i Ring structures b Disaccharide c Polysaccharide i Storage ii Structural Carbohydrates Sugars or polymers of sugars Monomer monosaccharide or sugar Bond glycosidic bond Monosaccharide simplest monomer Disaccharides double sugar 2 monomers joined by dehydration synthesis Polysaccharides storage starch glycogen structural cellulose Function primarily as energy source energy storage structural molecules source of carbon to make other organic molecules A Monosaccharide single sugar Sugars contain C H O in fixed ration CH20 3 7 carbons sugar molecule common ones triose 3C pentose 5C hexose 6C each carbon in sugar has a hydroxyl OH group attatched to it except one which is the carboxyl carbon C O in H20 solution like inside cells these monosaccharides tend to form ring structures reaction is reversible but ring is favored ex glucose a specific hexose BIO 101 1st Edition B Disaccharides 2 monosaccharides joined by a glycosidic bond Ex Maltose 2 glucoses joined by dehydration synthesis important disaccharide used in brewing beer In maltose the glycoside bond joins C 1 of one glucose to C 4 of another glucose Other disaccharides examples glucose 6C galactoste lactose milk sugar Glucose 6C fructose 5C sucrose table sugar C Polysaccharides macromolecules formed by linking 100s to 1000s of monosaccharide s by glycosidic bonds 1 Storage Polysaccharides molecules used to store energy Ex Starch major storage polysaccharide in plants a polymer of glucose connected by What is a and 1 4 glycosidic bonds glycosidic bond Glucose froms 2 inconvertible ring forms called glucose which differ in placement of OH group on C 1 glucose has OH BELOW plane of the ring ring Starch is made of glucoses in the glucose has OH above pane of the form 1 4 bonds BIO 101 1st Edition Most animals have enzyme that catalyzes the chemical reaction to break this bond can use starch as a source of energy ex Glycogen major storage polysaccharide in animals polymer of glucose more branched than starch stored mostly in liver and muscle 2 Structural Polysaccharides help form a structure ex cellulose forms structural reinforcement in plant cell walls linear unbranched polymer of glucose connected by 1 4 glycosidic bonds polymer similar to starch BUT most organisms cannot hydrolyze glucose monomers from cellulose WHY Enzyme does not recognize from 1 4 linkage it looks different 1 4 linkage ex Chitin structural polysaccharide of an amino sugar forms the exoskeleton of arthropods roach crunch Form cell walls of some fungi
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