Prokaryotic cells, as well as eukaryotic cells, both are two fundamental classes of cells. All organisms are formed from the basic fundamental unit of life i.e. cells. Human is a eukaryote. Human cells are eukaryotic cells. Eukaryotes having membrane-bound organelles, including the primitive nucleus. Bacteria is a prokaryote. Prokaryotes don’t have a nucleus or any other membrane-bound organelles.
Difference Between Eukaryotic Cells vs Prokaryotic Cells:
In this article, we are going to discuss the main differences between the eukaryotes (like Human body) and prokaryotes (like Bacteria).
| S.N. | Characteristics | Prokaryotes | Eukaryotes |
| 1. | Term Origin | ‘pro’ = pre, ‘karyon’= nucleus; Greek for “primitive nucleus” | ‘eu’ = true, ‘karyo’ = nucleus; Greek for “true nucleus” |
| 2. | Definition | Organisms made up of the cell(s) that lack a cell nucleus or any membrane-bound organelles. | Organisms made up of cells that possess a membrane-bound nucleus as well as membrane-bound organelles. |
| 3. | Major groups | Bacteria, Archaea, and Bluegreen algae. | Algae, fungi, protozoa, plants, animals. |
| 4. | Origin | Around 3.5 billion years ago. | Around 2 billion years ago. |
| 5. | Size (approximate) | 0.5-3.0 μm | >5 μm |
| 6. | Cell Type | Usually unicellular (some cyanobacteria may be multicellular) | Usually multicellular |
| 7. | Complexity | Simple organization. | Complex organization. |
| 8. | Nucleus Location | Free in the cytoplasm, attached to mesosomes. | Contained in membrane-bound structure. |
| 9. | Nuclear membrane | No nuclear membrane. | Double membrane present. |
| 10. | Nucleolus | Absent in this. | Present. |
| 11. | Chromosome number | One | More than one |
| 12. | Chromosome shape | Circular | Linear |
| 13. | Genes | Expressed in groups called operons. | Expressed individually |
| 14. | Genome | DNA haploid genome | DNA diploid genome |
| 15. | DNA base ratio (G+C %) | Near about 28-73 | about 40 |
| 16. | DNA wrapping on proteins | Multiple proteins act together to fold and condense prokaryotic DNA. Folded DNA is then organized into a variety of conformations that are supercoiled and wound around tetramers of the HU protein. | Eukaryotes wrap their DNA around proteins called histones. |
| 17. | Genome nature | Efficient and compact with little repetitive DNA. | This present with large amounts of non-coding repetitive DNA. |
| 18. | Membrane-bound organelles | Absent | Both membrane-bound and lack membrane-bound organelles present. |
| 19. | Ribosomes (sedimentation coefficient) | 70S (50S + 30S). Smaller unit present. | 80S (60S + 40S). Larger unit present. |
| 20. | Ribosome’s location | Free in the cytoplasm or bound to the cell membrane. | Attached to rough endoplasmic reticulum and also found freely in the cytoplasm. |
| 21. | Mitochondria | Absent | Present. |
| 22. | Golgi bodies | Absent | Present. |
| 23. | Endoplasmic reticulum | Absent | Present. |
| 24. | Mesosomes | Present. Performs the function of Golgi bodies and mitochondria and also help in the separation of the chromosome during cell division. | Absent |
| 25. | Lysosomes | Absent | Present |
| 26. | Peroxisomes | Absent | Present |
| 27. | Chloroplasts | Absent; chlorophyll scattered in the cytoplasm | Present (in plants) |
| 28. | Fimbriae | Prokaryotes may have pili and fimbriae (the appendage that can be found on many Gram-negative and some Gram-positive bacteria). | Absent |
| 29. | Microtubules | Absent. | Present |
| 30. | Centrosome | Absent | Present in animals cell. |
| 31. | Cytoskeleton | May be absent | Present |
| 32. | Glycocalyx | Present | Only in some |
| 33. | Cytoplasmic streaming | Absent | Present |
| 34. | Cytoplasmic membrane | Sterols absent (except Mycoplasma) | Contains sterols. |
| 35. | Cell wall | Complex hard structure made up of protein, lipids, and peptidoglycans. | Present for plant cells and fungi; otherwise absent |
| 36. | Muramic acid | Present | Absent |
| 37. | Movement | Simple flagellum, if present | Complex flagellum, if present |
| 38. | Respiration | Through cytoplasmic membrane. | By mitochondria. |
| 39. | Energy production site | Electron transport chain found in the cell membrane | Inside membrane-bound mitochondria |
| 40. | Metabolic rate | Higher due to the larger surface area to volume ratio. | Comparatively slow than a prokaryotic cell. |
| 41. | Reproduction | Only asexual (binary fission) | Both sexual and asexual reproduction present. Mitotic division |
| 42. | Generation time | Shorter | Relatively longer. |
| 43. | Genetic Recombination | Partial, unidirectional transfer | Meiosis and fusion of gametes occur. |
| 44. | Zygote | Merozygotic (partially diploid) | Diploid(2n) cell. |
| 45. | Extrachromosomal DNA | Occur in Plasmid. | Inside the mitochondria. |
| 46. | DNA replication | occurs in the cytoplasm. | Occurs in the nucleus. |
| 47. | Transcription and translation | occur simultaneously. | Transcription occurs in the nucleus and then translation occurs in the cytoplasm. |
Also Read: Cytokines- Mechanism of action and Functions