Makindo Medical Notes

Related Subjects: |Basic Chemistry for Medicine

Basic Chemistry for Medicine

Understanding basic chemistry is essential for medical professionals as it provides a foundation for comprehending various physiological processes, drug interactions, and diagnostic tests. This guide covers fundamental concepts of chemistry relevant to medicine.

Atoms and Molecules

• Atoms:
  • Basic unit of matter consisting of a nucleus surrounded by electrons.
  • Nucleus contains protons (positive charge) and neutrons (neutral charge).
  • Electrons (negative charge) orbit the nucleus in electron shells.
• Molecules:
  • Formed by the chemical bonding of two or more atoms.
  • Types of bonds: Ionic bonds (transfer of electrons), covalent bonds (sharing of electrons), and hydrogen bonds (weak bonds between hydrogen and electronegative atoms).

Chemical Reactions

• Types of Reactions:
  • Combination reactions: Two or more substances combine to form one product (e.g., A + B → AB).
  • Decomposition reactions: A single compound breaks down into two or more products (e.g., AB → A + B).
  • Displacement reactions: An atom or ion in a compound is replaced by an atom or ion of another element (e.g., AB + C → AC + B).
  • Redox reactions: Involves the transfer of electrons between two species, resulting in oxidation and reduction (e.g., 2Fe²⁺ + Cl₂ → 2Fe³⁺ + 2Cl⁻).
• Reaction Rates:
  • Factors affecting reaction rates: Temperature, concentration, surface area, and the presence of catalysts.

Solutions and Concentrations

• Solutions:
  • Homogeneous mixtures of two or more substances.
  • Solvent: The substance in which the solute is dissolved (e.g., water).
  • Solute: The substance dissolved in the solvent (e.g., salt).
• Concentration:
  • Amount of solute dissolved in a given volume of solvent.
  • Units of concentration: Molarity (moles per liter), molality (moles per kilogram of solvent), and percent solutions (e.g., w/v%, v/v%).

Acids, Bases, and pH

• Acids:
  • Substances that release hydrogen ions (H⁺) in solution.
  • Examples: Hydrochloric acid (HCl), sulfuric acid (H₂SO₄).
• Bases:
  • Substances that release hydroxide ions (OH⁻) in solution.
  • Examples: Sodium hydroxide (NaOH), potassium hydroxide (KOH).
• pH:
  • Measure of the hydrogen ion concentration in a solution.
  • pH scale ranges from 0 to 14, with 7 being neutral, below 7 acidic, and above 7 basic.
  • Physiological pH: Blood pH is tightly regulated between 7.35 and 7.45.

Buffers

• Substances that resist changes in pH by neutralizing added acids or bases.
• Important in maintaining the pH of blood and other bodily fluids.
• Examples: Bicarbonate buffer system, phosphate buffer system, protein buffer system.

Biomolecules

• Carbohydrates:
  • Primary source of energy for the body.
  • Monosaccharides (e.g., glucose), disaccharides (e.g., sucrose), polysaccharides (e.g., glycogen, starch).
• Proteins:
  • Composed of amino acids linked by peptide bonds.
  • Functions: Enzymes, structural proteins, hormones, antibodies.
• Lipids:
  • Composed of fatty acids and glycerol.
  • Functions: Energy storage, cell membrane structure, signaling molecules.
• Nucleic Acids:
  • Composed of nucleotides (sugar, phosphate, nitrogenous base).
  • Types: DNA (genetic material), RNA (protein synthesis).

Summary

Basic chemistry is fundamental for understanding physiological processes, drug interactions, and medical diagnostics. Key concepts include the structure of atoms and molecules, chemical reactions, solutions and concentrations, acids and bases, buffers, and biomolecules. Mastery of these concepts is essential for medical professionals to effectively diagnose and treat patients.