SM

Cell Biology & Chemistry Essentials

Eukaryotes vs. Prokaryotes

  • Eukaryotes: Have a nucleus and many other membrane-bound organelles (e.g., mitochondria, chloroplasts, lysosomes, ER).

  • Prokaryotes: Do not have membrane-bound organelles or a nucleus. They possess ribosomes, a plasma membrane, DNA, and cytoplasm.

pH Scale

  • pH below 7 (e.g., 0 to 6.9): Acidic. High concentration of hydrogen ions (H^+).

  • pH above 7 (e.g., 7.1 to 14): Basic (alkaline). Low concentration of hydrogen ions (H^+).

  • pH 7: Neutral.

Electronegativity

  • Tendency of an atom (typically oxygen or nitrogen) to attract electrons.

  • Involved in hydrogen bonding.

Hydrophilic vs. Hydrophobic

  • Hydrophilic (water-loving):

    • Chemicals soluble in water.

    • Molecules must be charged or polar (partially charged) to dissolve in water.

  • Hydrophobic (water-fearing): Not soluble in water.