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Lesson 1 - The Biomolecules: Introduction and the Carbohydrates

Student Performance Objectives
1. Explain the difference between inorganic and organic compounds.
2. Give three examples of the functional groups found on organic molecules.
3. Define molecule, macromolecule, monomer and polymer.
4. Describe and give an example of a monosaccharide, a disaccharide and a polysaccharide.

Lesson Outline
A. Introductory concepts
    1. Concept of organic compounds and the importance of the carbon atom as the
        backbone for the biologically interesting molecules.
        Try this atom builder:
    2. Concept of functional groups.
        a. Hydroxyl groups (OH) as seen on sugars like glucose.
        b. Amino groups (NH2) as seen on amino acids, the building blocks of the proteins.
        c. Carboxyl or organic acid groups (COOH) as seen on amino acids other acids like acetic acid.
        d. Phosphate groups (PO4) as seen on ATP, the high-energy molecule of the cell, and in the nucleic acids like DNA and RNA.
        e. Methyl groups (CH3) as seen on amino acids and triglycerides.
    3. Concept of the molecule and the macromolecule.
    4. Concept of the monomer and the polymer: use glycogen formation from glucose as an
B. Carbohydrates
    1. Definition and general information
        a. Yield 4 kcal/g when oxidized for energy.
        b. Main cellular fuel in general. Central nervous system uses glucose for energy
            almost exclusively.
        c. Contain carbon, hydrogen and oxygen in the ratio: CH2O.
   2. Monosaccharides
        a. Glucose: blood sugar. Structure:   
            The following site shows the shifting of the glucose molecule between its
            linear and ring forms:
        b. Fructose: fruit sugar.
        c. Galactose: part of milk sugar.
        d. Ribose and deoxyribose: sugars found in nucleic acids, DNA and RNA.
    3. Disaccharides
        a. Sucrose: combination of glucose and fructose. Structure:
        b. Lactose: combination of glucose and galactose.
        c. Maltose: combination of glucose and galactose.
    4. Polysaccharides
        a. Starch: "n" glucose molecules in plants as a storage molecule. Structure:
        b. Glycogen: "n" glucose molecules in animals as a storage molecule. 
        c. Cellulose: "n" glucose molecules in plants as a structural component. 
    5. For a molecular view of the differences between monosaccharides, disaccharides, and