07_Hierarchical_Terms

Home > Key Terms & Concepts

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Key Terms & Concepts

• Carbon’s Role in Biological Molecules
  • Organic Molecule
    • Definition: Substance containing carbon
    • Vital for life
  • Macromolecules
    • Proteins
    • Nucleic acids
      • RNA
      • DNA
    • Carbohydrates
    • Lipids
  • Foundational building block
• Carbon Atom Structure
  • Atomic number: 6
  • Electron distribution
    • 2 inner shell
    • 4 outer shell (valence)
  • Octet Rule
    • Achieve 8 electrons in outermost shell
  • Covalent bonds
    • Forms up to four
    • Forms strong bonds
  • Flexibility (main structural component)
  • Methane (CH4) example
    • Carbon bonded to 4 hydrogen atoms
    • Tetrahedral geometry
• Hydrocarbons
  • Definition: Made entirely of carbon and hydrogen
  • Energy storage
    • Numerous covalent bonds
    • Released when molecules burn (oxidize)
  • Molecular shape (conformation)
    • Crucial to how they function
• Hydrocarbon Chains: Types and Geometries
  • Chain structures
    • Straight chains
    • Branched chains
    • Unbranched chains
    • Combinations (of chains and rings)
  • Carbon-carbon bond types
    • Single covalent bonds
      • Suffix: -ane
      • Geometry: Tetrahedral
      • Characteristic: Allows rotation around bond axis
      • Example: Ethane
    • Double covalent bonds
      • Suffix: -ene
      • Geometry: Planar (flat)
      • Characteristic: Cannot rotate
      • Example: Ethene
    • Triple covalent bonds
      • Suffix: -yne
      • Geometry: Linear (straight)
      • Characteristic: Highly restricted rotation
      • Example: Ethyne
  • Nomenclature
    • Prefixes (e.g., eth- for two carbons)
    • Suffixes (-ane, -ene, -yne for bond type)
• Hydrocarbon Rings: Aliphatic and Aromatic
  • Aliphatic hydrocarbons
    • Characteristics: Linear chains OR rings with only single bonds
    • Ring examples: Cyclopentane, Cyclohexane
  • Aromatic hydrocarbons
    • Characteristics: Closed rings with alternating single and double bonds
    • Benzene ring example
      • Incorporated into biological molecules
      • Biological examples: amino acids, cholesterol, hormones (estrogen, testosterone)
      • Other examples: herbicide 2,4-D
      • Health risk: Carcinogen
  • Mixed structures
    • Contain both aliphatic and aromatic parts
    • Example: Beta-carotene

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See also: 03_Study_Guide