Key Differences Between Prokaryotic and Eukaryotic Cells

Overview

• Prokaryotic Cells

  • Simplest and most ancient cells.
  • Only form of life on Earth for billions of years.
  • Smaller and have a simpler structure compared to eukaryotic cells.
  • Quick and effective reproduction due to simple structure.

• Eukaryotic Cells

  • Evolved from prokaryotic cells.
  • Larger and more complex structure.
  • Contain membrane-bound nucleus and organelles.

Structure

• Prokaryotic Cells

  • Lack a nucleus ("Prokaryote" means "before nucleus").
  • No membrane-bound organelles.
  • DNA located in the nucleoid region (not enclosed by a membrane).
  • Presence of ribosomes scattered throughout the cytoplasm.
  • Cell wall surrounds the plasma membrane, composed of complex polysaccharides.
  • Often possess flagella for movement.

• Eukaryotic Cells

  • Contain a membrane-bound nucleus ("Eukaryote" means "true nucleus").
  • Organelles are membrane-bound.

Commonalities

• Both have:
  • DNA as genetic material.
  • Ribosomes.
  • Cytoplasm.
  • Plasma membrane.

Differences

• Age and Complexity

  • Prokaryotic cells are older, smaller, and simpler.
  • Eukaryotic cells evolved later and are larger, more internally complex.

• Nucleus and Organelles

  • Prokaryotes lack both a nucleus and membrane-bound organelles.
  • Eukaryotes have a nucleus and organelles.

• Cellularity

  • Prokaryotes are single-celled organisms.
  • Eukaryotes can be single-celled or multicellular.

• DNA Structure

  • Prokaryotic DNA is usually a single, circular chromosome.
  • Eukaryotic DNA is organized into linear chromosomes.