Chemical Level of Organisation

Introduction to Chemistry in Paramedic Science

  • Chemistry: The study of the composition and properties of matter.
  • Understanding of chemistry aids in:
    • Normal and abnormal body functioning (e.g., digestion, urine production, breathing).
    • Pharmacology: Development and understanding of chemicals used in treatment of diseases.

Matter & Elements

  • Matter: Anything that occupies space; all substances in the universe.
  • Elements: Unique substances making up matter; 92 naturally occurring elements.
  • Examples of elements:
    • Gases: Hydrogen (H), Oxygen (O), Nitrogen (N)
    • Solids: Iron (Fe), Zinc (Zn)
    • Carbon (C): Vital for proteins, carbohydrates, fats; crucial for body physiology.
    • Carbon-containing gaseous and liquid compounds impact body functions.

Elemental Composition of the Human Body

  • Major elements include:
    • Water (H₂O): 62%
    • Oxygen (O): 65%
    • Carbon (C): 18%
    • Hydrogen (H): 9.5%
    • Nitrogen (N): 3.2%
    • Minerals (e.g., Calcium, Sodium, Potassium) and other components make up remaining percentage.

Structure of Atoms

  • Atoms: Basic units of chemical elements, consisting of:
    • Nucleus: Contains protons and neutrons.
    • Electrons: Orbitals surrounding the nucleus in an electron cloud.
  • Protons (p⁺): Positively charged particles in the nucleus.
  • Neutrons (n⁰): Neutral particles in the nucleus, contribute to mass.
  • Electrons (e⁻): Extremely small, with negligible mass compared to protons/neutrons.
  • Atoms are neutral due to equal numbers of protons and electrons.

Ions, Molecules, & Compounds

  • Ions: Atoms that have lost or gained electrons; indicated by charges (e.g., Na⁺).
  • Molecules: Formed by atoms sharing electrons (e.g., H₂O, O₂).
  • Chemical Bonds:
    • Ionic bonds: Formed through electron transfer.
    • Covalent bonds: Formed through electron sharing (strongest type).

Chemical Bonds

  • Ionic Bonds:
    • Formation due to transfer of electrons between atoms (e.g., NaCl).
    • Cations (+): E.g., Na⁺, Anions (-): E.g., Cl⁻.
  • Covalent Bonds:
    • Can be single, double, or triple bonds based on shared electron pairs.
    • Nonpolar: Equal sharing of electrons.
    • Polar: Unequal sharing, critical for water's properties.
  • Hydrogen Bonds:
    • Weak attractions between hydrogen and electronegative atoms (e.g., in water).

Chemical Reactions

  • Defined as interactions involving the sharing or transferring of electrons leading to bond alterations.
  • Metabolism: Overall chemical reactions occurring in the body.
  • Types of reactions:
    • Synthesis (Anabolism): A + B ➙ AB
    • Decomposition (Catabolism): AB ➙ A + B
    • Exchange: AB + CD ➙ AD + CB
    • Reversible: AC ↔ A + C

Inorganic & Organic Compounds

  • Inorganic Compounds: Lack carbon, simple molecular structures (e.g., KCl).
  • Organic Compounds: Always contain carbon, often large and complex, typically with hydrogen.

Water and its Properties

  • Water as a solvent: Forms solutions by dissolving solutes (e.g., salt in water).
  • Properties of water:
    • High Heat Capacity: Absorbs/releases heat with minimal temperature change.
    • Heat Vaporization: High amounts of heat energy needed for phase change (liquid to gas).

Common Mixtures

  • Mixtures: Physical combinations of elements or compounds; properties vary by type.
    • Solutions: Combinations where solute is dissolved (most common in the body is water).
    • Suspensions: Components may eventually settle (e.g., blood).
    • Colloids: Molecules remain evenly distributed without dissolution (e.g., cytosol, blood plasma).