Prokaryotic and eukaryotic cells are two fundamental types of cells that make up all living organisms. Here’s a comparison and contrast of these two cell types:
Prokaryotic Cells
- Definition: Simple, unicellular organisms without a nucleus.
- Nucleus: No true nucleus; genetic material (DNA) is located in a nucleoid region.
- Size: Typically smaller (0.1-5.0 micrometers in diameter).
- Organelles: Lack membrane-bound organelles; ribosomes are present but smaller than in eukaryotes.
- Cell Wall: Most have a rigid cell wall composed of peptidoglycan (in bacteria).
- Reproduction: Asexual reproduction primarily through binary fission.
- Examples: Bacteria and Archaea.
Eukaryotic Cells
- Definition: More complex cells that can be unicellular or multicellular, containing a nucleus.
- Nucleus: True nucleus enclosed by a nuclear membrane.
- Size: Generally larger (10-100 micrometers in diameter).
- Organelles: Contain membrane-bound organelles, including mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosomes.
- Cell Wall: In plants, the cell wall is primarily composed of cellulose; fungi have chitin.
- Reproduction: Asexual and sexual reproduction; encompasses more complex life cycles.
- Examples: Animals, plants, fungi, and protists.
Similarities
- Genetic Material: Both cell types have genetic material (DNA).
- Ribosomes: Both types have ribosomes for protein synthesis, although they differ in size.
- Plasma Membrane: Both are enclosed by a plasma membrane.
Mitochondria
Mitochondria are found only in eukaryotic cells. They are known as the powerhouse of the cell, as they generate ATP through aerobic respiration. No prokaryotic cells possess mitochondria; instead, they carry out respiration across their plasma membrane.
Summary
- Mitochondria are characteristics of eukaryotic cells, not prokaryotic cells.
- Prokaryotic cells are simpler and smaller with no nucleus or membrane-bound organelles, while eukaryotic cells are more complex with a defined nucleus and various organelles, including mitochondria.