Chemistry: The Logic of Biological Phenomena in Biochemistry, 2nd Edition

1. CHAPTER 1 Chemistry is the Logic of Biological Phenomena to accompany Biochemistry, 2/e by Reginald Garrett and Charles Grisham All rights reserved. Requests for permission to make copies of any part of the work should be mailed to: Permissions Department, Harcourt Brace & Company, 6277 Sea Harbor Drive, Orlando, Florida 32887-6777

2. Outline • 1.1 Distinctive Properties of Living Systems • 1.2 Biomolecules: Molecules of Life • 1.3 Biomolecular Hierarchy • 1.4 Properties of Biomolecules • 1.5 Organization and Structure of Cells • 1.6 Viruses as Cell Parasites

3. On Life and Chemistry... • “Living things are composed of lifeless molecules” (Albert Lehninger) • “Chemistry is the logic of biological phenomena” (Garrett and Grisham)

4. 1.1 Distinctive Properties of Living Systems • Organisms are complicated and highly organized • Biological structures serve functional purposes • Living systems are actively engaged in energy transformations • Living systems have a remarkable capacity for self-replication

8. 1.2 Biomolecules: The Molecules of Life H, O, C and N make up 99+% of atoms in the human body ELEMENTPERCENTAGE Oxygen 63 Hydrogen 25.2 Carbon 9.5 Nitrogen 1.4

9. 1.2 Biomolecules: The Molecules of Life • What property unites H, O, C and N and renders these atoms so appropriate to the chemistry of life? • Answer: Their ability to form covalent bonds by electron-pair sharing.

10. 1.2 Biomolecules: The Molecules of Life What are the bond energies of covalent bonds? BondEnergy kJ/mol H-H 436 C-H 414 C-C 343 C-O 351

13. 1.3 A Biomolecular Hierarchy Simple Molecules are the Units for Building Complex Structures • Metabolites and Macromolecules • Organelles • Membranes • The Unit of Life is the Cell

15. 1.4 Properties of Biomolecules Reflect Their Fitness to the Living Condition • Macromolecules and Their Building Blocks Have a “Sense” or Directionality • Macromolecules are Informational • Biomolecules Have Characteristic Three-Dimensional Architecture • Weak Forces Maintain Biological Structure and Determine Biomolecular Interactions

21. 1.4 Properties of Biomolecules Reflect Their Fitness to the Living Condition Important numbers! • van der Waals: 0.4-4.0 kJ/mole • Hydrogen bonds: 12-30 kJ/mole • Ionic bonds: 20 kJ/mole • Hydrophobic interactions: <40 kJ/mole

23. Two Important Points About Weak Forces • Biomolecular Recognition is Mediated by Weak Chemical Forces • Weak Forces Restrict Organisms to a Narrow Range of Environmental Conditions

28. Organization and Structure of Cells • Prokaryotic cells • A single (plasma) membrane • no nucleus or organelles • Eukaryotic cells • much larger in size than prokaryotes • 103-104 times larger! • Nucleus plus many organelles • ER, Golgi, mitochondria, etc.