𧬠What are Prokaryotic Ribosomes?
Prokaryotic ribosomes are found in bacteria and archaea. They are smaller and less complex than their eukaryotic counterparts. Think of them as the reliable workhorses of the simpler cells.
π¬ What are Eukaryotic Ribosomes?
Eukaryotic ribosomes are found in plants, animals, fungi, and protists. They are larger and more complex than prokaryotic ribosomes, reflecting the increased complexity of eukaryotic cells. They are the sophisticated protein-making machines of complex life.
π Prokaryotic vs. Eukaryotic Ribosomes: A Side-by-Side Comparison
| Feature |
Prokaryotic Ribosomes |
Eukaryotic Ribosomes |
| Location |
Cytoplasm |
Cytoplasm, Rough Endoplasmic Reticulum (RER), Mitochondria, Chloroplasts |
| Size |
70S (30S and 50S subunits) |
80S (40S and 60S subunits) |
| rRNA Molecules |
16S rRNA (small subunit), 23S rRNA and 5S rRNA (large subunit) |
18S rRNA (small subunit), 28S rRNA, 5.8S rRNA and 5S rRNA (large subunit) |
| Proteins |
~55 proteins |
~80 proteins |
| Sensitivity to Antibiotics |
More sensitive (target for many antibiotics) |
Less sensitive |
| Complexity |
Less complex |
More complex |
π Key Takeaways
- π Location Matters: Prokaryotic ribosomes are solely in the cytoplasm, while eukaryotic ribosomes are found in multiple locations.
- π’ Size Difference: Eukaryotic ribosomes (80S) are larger than prokaryotic ribosomes (70S). The 'S' stands for Svedberg units, a measure of sedimentation rate during centrifugation.
- π§ͺ Subunit Composition: The subunits differ in size and composition, with prokaryotic ribosomes having 30S and 50S subunits, and eukaryotic ribosomes having 40S and 60S subunits.
- 𧬠rRNA Variety: The types of ribosomal RNA (rRNA) molecules differ between the two types.
- π‘ Antibiotic Targets: The structural differences make prokaryotic ribosomes targets for many antibiotics, which can selectively inhibit bacterial protein synthesis without harming eukaryotic cells.