compare the structure of a prokaryotic cell as found in a typical bacterium with the structures of typical eukaryotic cells in plants and animals

Sourav PanOctober 28, 2024

Answered step-by-step

Here’s a comparison of the structures of a typical prokaryotic cell (like a bacterium) and eukaryotic cells (both plant and animal cells):

1. Nucleus

• Prokaryotic Cell: Lacks a nucleus; genetic material (DNA) is found in a region called the nucleoid, which is not membrane-bound.
• Eukaryotic Cells: Have a true nucleus surrounded by a nuclear membrane, containing DNA arranged in multiple chromosomes.

2. DNA Structure

• Prokaryotic Cell: Has circular DNA (single chromosome) without histone proteins and sometimes includes extra plasmids (small, circular DNA).
• Eukaryotic Cells: DNA is linear and organized around histone proteins into chromosomes, contained within the nucleus.

3. Ribosomes

• Prokaryotic Cell: Has 70S ribosomes scattered in the cytoplasm, which are smaller than eukaryotic ribosomes.
• Eukaryotic Cells: Possess 80S ribosomes, which are larger and found in the cytoplasm and on the rough endoplasmic reticulum (ER). Mitochondria and chloroplasts contain their own 70S ribosomes, similar to prokaryotes.

4. Cell Wall

• Prokaryotic Cell: Most have a rigid cell wall made of peptidoglycan for structural support.
• Plant Cells: Have a cell wall made of cellulose, providing structure and support.
• Animal Cells: Do not have a cell wall; they are surrounded by a flexible plasma membrane.

5. Membrane-Bound Organelles

• Prokaryotic Cell: No membrane-bound organelles, like mitochondria or ER.
• Eukaryotic Cells: Contain various membrane-bound organelles:
  • Mitochondria: For energy production.
  • Chloroplasts (in plant cells): For photosynthesis.
  • Endoplasmic Reticulum (ER): Rough ER for protein synthesis, smooth ER for lipid synthesis.
  • Golgi Apparatus: For modifying and packaging proteins.
  • Lysosomes (mainly in animal cells): For waste processing and digestion.

6. Cytoplasm

• Prokaryotic Cell: Consists of a simpler cytoplasm with no cytoskeleton.
• Eukaryotic Cells: The cytoplasm is complex, with a cytoskeleton made of microtubules and filaments, supporting cell shape and enabling intracellular transport.

7. Reproduction

• Prokaryotic Cell: Reproduce asexually through binary fission, a simpler division process.
• Eukaryotic Cells: Reproduce via mitosis (for growth) and meiosis (for sexual reproduction), involving complex steps.

8. Other Structures (Flagella, Pili, Capsule)

• Prokaryotic Cell: Some have a capsule for protection, pili for attachment, and flagella for movement.
• Eukaryotic Cells: Animal cells may have flagella or cilia for movement (e.g., sperm cells have flagella), but not pili or a capsule.