Understanding Prokaryotic and Eukaryotic Cells

Introduction

  • Personal anecdote about a circular red spot on arm from elementary school.
  • Initial belief: Spot was caused by a ring-shaped worm due to the name "ringworm".

Understanding Ringworm

  • Definition of Ringworm: Ringworm is not caused by a worm but by a fungus.
  • Common carriers of ringworm: Pets and soil.
  • Personal experience with treatment: Instead of antibiotics, treated with antifungal cream, leading to recovery.
  • Reflection on treatment: Questioned the difference between antibiotics and antifungals.

Antibiotics vs. Antifungals

  • Function of Antibiotics:
    • Destroy bacteria by:
      • Affecting their ability to reproduce.
      • Damaging cell walls.
      • Interfering with protein synthesis necessary for survival.
  • Bacterial cells vs. Fungal cells: Fundamental differences exist.
  • Comparison of Cell Types:
    • Fungal cells resemble animal cells more closely than bacterial cells do.

Cell Theory and Classification of Life

  • Modern Cell Theory Statement: All living things are made of one or more cells.
  • Three Domains of Life:
    • Prokaryotes:
    • Type: Bacteria and Archaea.
    • Characteristics: Unicellular (single-celled organisms).
    • Eukaryotes:
    • Classification: Organisms in the domain Eukarya.
    • Types: Include Protists, Plants, Animals, and Fungi.
    • Life Forms: Can be unicellular or multicellular (e.g., humans).

Definitions: Prokaryote and Eukaryote

  • Prokaryote: Refers to both the organism and the corresponding cell type (prokaryotic cell).
  • Eukaryote: Refers to both the organism and the corresponding cell type (eukaryotic cell).

Similarities between Prokaryotic and Eukaryotic Cells

  • Both contain:
    • DNA: Critical as genetic material.
    • Ribosomes: Small organelles responsible for protein synthesis (analogous to tiny organs).
    • Cytoplasm: Jelly-like fluid within the cells.
    • Cell Membrane (Plasma Membrane): Controls entry and exit of substances, maintaining homeostasis.

Differences between Prokaryotic and Eukaryotic Cells

  • Cellular Structure:
    • Prokaryotic cells are generally smaller and simpler.
  • Nucleus:
    • Prokaryotic cells:
    • Lack a nucleus; DNA is not contained within a membrane.
    • Eukaryotic cells:
    • Have a nucleus to keep DNA enclosed.
  • Organelles:
    • Prokaryotic cells:
    • Do not have membrane-bound organelles (e.g., mitochondria, Golgi apparatus).
    • Eukaryotic cells:
    • Possess membrane-bound organelles; diversity based on cell type.

Examples of Eukaryotic Cell Types

  • Plant cells: likely to have chloroplasts.
  • Animal cells: do not have chloroplasts.

Importance of Cell Classification

  • Understanding characteristics of prokaryotic and eukaryotic cells enhances understanding of living diversity:
    • Includes all life forms: Archaea, Bacteria, Protists, Fungi, Plants, Animals.
  • Infections identification: Knowing if it involves prokaryotic or eukaryotic cells can guide treatment options.

Conclusion

  • Reminder to stay curious, learn about cell types and their impact in real-world applications such as infection treatment.