Prokaryotes vs Eukaryotes (Differences)
As biologists, we should definitely be aware of the key difference between prokaryotic cells and eukaryotic cells. Prokaryotic cells can be clearly distinguished from eukaryotic cells in terms of their molecular make-up and cell structure. Generally, the prokaryotes have a comparatively simpler structure as compared to eukaryotes. Have you ever wondered on what basis the cells are classified as prokaryotes and eukaryotes? This classification is usually done on the basis of the organisation of genetic material (DNA). Do not worry! It is very simple!
- The cells in which the genetic material is not seen to be enclosed in an envelope, are referred to as prokaryotes. Thus, there is no presence of a membrane-bound true nucleus in prokaryotes.
Examples of Prokaryotes: Eubacteria, Cyanobacteria, Mycoplasma, Archaebacteria
- The cells in which the genetic material is seen to be enclosed in an envelope, are referred to as eukaryotes. Thus, there is a presence of a true nucleus in eukaryotes (membrane-bound nucleus).
Examples of Eukaryotes: Plants, Animals, Fungi.
Differences between Prokaryotes and Eukaryotes:
- Cell wall: Prokaryotes- Made up of peptidoglycan in Eubacteria and in Archaea, usually made of pseudomurein (pesudopeptidoglycan). Eukaryotes- Present in plants (chiefly made up of cellulose, hemicellulose and pectic substances) and in fungi (chiefly made of chitin). Absent in animal cells.
- Cell Size: Prokaryotes- Usually small (0.1-5.0 µm) whereas Eukaryotes-Large (5-100µm).
- Lipids of the membrane: Prokaryotes-Some branched hydrocarbons. Eukaryotes-Unbranched hydrocarbons.
- Membrane-bound organelles such as Golgi apparatus, ER, lysosomes etc: Prokaryotes-Absent. Eukaryotes-Present.
- Nuclear envelope: Prokaryotes-Absent whereas in Eukaryotes-Present.
- Histones: Prokaryotes-Absent whereas in Eukaryotes-Present (although archaebacteria do have histones which are different from eukaryotic histones).
- Chromosome: Prokaryotes-Circular whereas in Eukaryotes-Linear.
- Ribosomes: Prokaryotes-70S type while in Eukaryotes- 80S type (in the cytosol) and 70S (in organelles)
- Thylakoids: Prokaryotes-If present, lie free in the cytoplasm. Eukaryotes-Thylakoids group as chloroplasts.
- Introns: Prokaryotes-Absent while in Eukaryotes-Present. However, archaebacteria do have introns.
- Initiator amino acid at the time of protein synthesis: Prokaryotes-Formyl-methionine. Eukaryotes-Methionine.
- RNA polymerase: Prokaryotes-One type in eubacteria but of several types in archaea. Eukaryotes-Several types (I,II,III).
- Response to antibiotics such as streptomycin and chloramphenicol: Prokaryotes-Growth gets inhibited. Eukaryotes-Growth is not
inhibited. - Spindle apparatus formation during division: Prokaryotes-It does not form in this case. Eukaryotes-It forms in this case
- Transcription and Translation: Prokaryotes-These processes occur in the cytoplasm. Eukaryotes-Transcription occurs in the nucleus while translation occurs in the cytoplasm.
- Sterol in the plasma membrane: Absent (except Mycoplasma). Eukaryotes-Present.
For more differences check- https://mybiologydictionary.com/category/differences/
Thank you for reading
Team MBD
For more images on eukaryotic cells, check out 1,096 Eukaryotic cell Stock Video Footage – 4K and HD Video Clips | Shutterstock