Cell Types: Eukaryotes vs Prokaryotes

  • Categorization of Cells: Two main groups of cells: Eukaryotes and Prokaryotes.

  • Definitions:

    • Eukaryotes: "True nut"; cells with genetic material enclosed in a nucleus.
    • Prokaryotes: "Before the nut"; cells without a nucleus enclosing their genetic material.

  • Examples of Eukaryotic Cells: Plants, animals, fungi, and protists.

  • Examples of Prokaryotic Cells: Bacteria and archaea.

  • Genetic Material:

    • Eukaryotic cells have DNA within a membrane-bound nucleus.
    • Prokaryotic cells have DNA in a loop form, not enclosed in a nucleus.

  • Cell Structure:

    • Eukaryotic:
    • Contains a cell membrane, cytoplasm, and a membrane-bound nucleus.
    • Prokaryotic:
    • Contains a cell wall, cytoplasm, and loops of DNA (DNA loop) and plasmids.
    • Lacks membrane-bound organelles like mitochondria.

  • Cell Size:

    • Eukaryotic cells: 10-100 micrometers (tiny).
    • Prokaryotic cells: approximately 1 micrometer.

  • Prokaryotic Cell Features:

    • No mitochondria; energy released through aerobic respiration not applicable.
    • Divide by binary fission (replicating and splitting into two identical daughter cells).

  • Key Terms:

    • Nucleus: Contains DNA and controls cell activities.
    • Cytoplasm: Fluid that suspends cell structures.
    • Cell Wall: Provides structure; different in prokaryotic cells compared to plant cell walls.