MCB 150 1st Edition Lecture 4 Outline of Last Lecture I. Structures and functions of organelles in a Eukaryotic cellsII. MacromoleculesOutline of Current Lecture III. Types of monosaccharidesa. Hexosesb. Triosesc. PentosesIV. Polysaccharidesa. Celluloseb. Starchc. GlycogenCurrent LectureMonosaccharides: usually found with 3, 5, or 6 carbons in the chain. Ex. Glucose ( C₆H₁₂O₆) linear and circular forms α-Glucose: When the carbon (1) is circularized with the H on top in the structural orientationβ-Glucose: When the carbon (1) is circularized with the hydroxyl group on top in the structural orientationCircularization of Glucose: The transition of the linear form of the glucose to the circular structure. Isomers: chemical compounds that have the same chemical formula but different structures Common in monosaccharides  Other times monosaccharides have SIMILAR formulas (not identical), structures and functions. Hexoses: 6-carbon sugars  Aldose: Glucose, GalactoseThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. Ketose: FructoseTrioses: 3- carbon sugars  Aldose: Glyceraldehyde Ketose: DihydroxyacetonePentoses: 5-carbon sugars  Aldose: RibosePolysaccharideDisaccharide: when two monosaccharides come together to form a simple polysaccharideGlycosidic linkage: Covalent bond that joins monosaccharidesDisaccharide of 2 hexose sugars has the formula, C₁₂H₂₂O₁₁Terminology:- One monomer is a: monosaccharide- Two monomers is a: disaccharide- Three or more is a : polysaccharide- Hundreds or thousands of monomers is a: oligosaccharideCarbohydrates can be modified:- Linkage of oligosaccharides to other macromolecules- Addition of chemical groupsPolysaccharides serve as chemical sources of energy or structural compounds:- Cellulose- Starch- GlycogenCellulose:- Most abundant organic compound on earth- Found in plant cell walls- Linear and unbranched polymer of glucoseo Linked monomers with a β-1,4 glycosidic linkageso Hydrogen bonds hold together linear polymers with adjacent strandsStarch:- Found mostly in seeds, fruits, tubers, and roots and stems of plants- Used in energy storage- Helical polymers if glucose that are either loosely branched or unbranchedo Monomers inside chains bonded with an α-1,4 glycosidic linkageo Chains connecting with one another by a α-1,6 glycosidic linkGlycogen:- Found in muscle and liver cells of animals- Used in energy storage- Highly branched molecules of glucose, helical n shapeo Monomers inside chain s linked with a α-1,4 glycosidic linko Chains connecting with one another with a α-1,6 glycosidic