AP Biology Unit 1: Biochemistry: Chapters 2, 3, 4 and 5 The chemical characteristics of a substance determine its role in an organism. Carbon and water are universally important to all organisms. The biological macromolecules – carbohydrates, proteins, lipids, nucleic acids – also play significant roles. Ions are integral to a variety of cellular activities because of their role in establishing electrochemical gradients. Learning Objectives The student is able to distinguish between covalent bonds, ionic bonds, hydrogen bonds, and van der Waals interactions. The student is able to describe the emergent properties of water and carbon. The student is able to explain the connection between the sequence and the subcomponents of a biological polymer and its properties. The student is able to analyze data to identify how molecular interactions affect structure and function. Vocabulary emergent property element atom isotope radioactive ion covalent bond ionic bond hydrogen bond van der Waals interactions polar covalent bond cohesion adhesion surface tension specific heat heat of vaporization aqueous solution hydrophillic hydrophobic acid base pH buffer electronegativity macromolecules polymers monomers enzymes dehydration reaction hydrolysis carbohydrates monosaccharides disaccharide polysaccharide starch glycogen cellulose lipids fat fatty acid glycerol saturated fatty acid unsaturated fatty acid trans fats phospholipids steroids cholesterol catalysts polypeptides protein amino acid peptide bond denaturation nucleic acids deoxyribonucleic acid (DNA) ribonucleic acid (RNA) nucleotides pyrimidine purine Analysis Questions 1. How do covalent bonds differ from ionic bonds? 2. How do hydrogen bonds differ from van der Waals interactions? 3. Describe the emergent properties of water. 4. Describe the emergent properties of carbon. 5. Describe the function of buffers and provide an example. 6. Create and complete the table below to describe the properties of the four major groups of macromolecules - carbohydrates, proteins, lipids, and nucleic acids. The carbohydrates column has already been completed for you Carbohydrates Atoms present C, H and O Polymer name(s) Polysaccharide Monomer name(s) Monosaccharide Functional groups present carbonyl (C=O), hydroxyl (-OH) Chemical properties due to functional groups can form hydrogen bonds, which help carbohydrates dissolve in water Functions of macromolecule energy storage, structural support Macromolecule Examples chitin, cellulose, glycogen, starch, Other Notes also called “sugar” 7. Proteins Lipids Nucleic Acids A dehydration reaction joins two glucose molecules to form maltose. The formula for glucose is C H O . What is the formula for maltose? 6 12 6 8. Distinguish between the 1°(primary), 2° (secondary), 3° (tertiary) and 4°(quaternary) structures of proteins. 9. What role do enzymes play in organisms? Review the website http://www.hsph.harvard.edu/nutritionsource/ as you answer questions 9 and 10. 10. Which types of fats are “good” for you to eat? Which are “bad?” Explain. What are the chemical properties of “good” fats and “bad” fats? 11. How many grams of protein do you need to eat each day? What are the healthiest sources of protein? Explain.