Prokaryotic and eukaryotic cells are found on earth. Prokaryotes are always unicellular, whereas eukaryotic cells are multicellular or unicellular. We will see the structural difference between prokaryotic and eukaryotic cells in detail when comparing and contrasting the structure of prokaryotic and eukaryotic by stating their similarities and differences separately. In 1937, French researcher Chatton created the Prokaryote/Eukaryote nomenclature to divide living beings into two main classes: prokaryotes (bacteria) and eukaryotes (organisms with nucleated cells).
The nucleus of eukaryotes is encased with a nuclear envelope. Eukaryotes are members of the Eukaryota or Eukarya domain; their name is derived from the Greek (eu, “well” or “good”) and (karyon, “nut” or “kernel”). The domain Eukaryota is one of three domains of life; the other two categories are bacteria and archaea (prokaryotes).
A single-celled creature without a nucleus and other membrane-bound organelles is known as a prokaryote. A prokaryote is derived from the Greek pro (‘before’) and (karyon, “nut” or “kernel”). Prokaryotes were classed into the empire Prokaryota in the two-empire system developed by Édouard Chatton. However, based on molecular research, prokaryotes are separated into two domains in the Prokaryote system: Bacteria ( Eubacteria) and Archaea (formerly Archaebacteria).
Structure of Prokaryotic and Eukaryotic cells
Prokaryotes have a cell wall surrounding the cell membrane. The fluid matrix filling the cell is the cytoplasm. There is no well-defined nucleus. The genetic material is basically naked, not enveloped by a nuclear membrane. In addition to the genomic DNA (the single chromosome/circular DNA), many bacteria have small circular DNA outside the genomic DNA. These smaller DNA are called plasmids. The plasmid DNA confers certain unique phenotypic characters to such bacteria. One such character is resistance to antibiotics. In higher classes you will learn that this plasmid DNA is used to monitor bacterial transformation with foreign DNA. Prokaryotes have something unique in the form of inclusions. A specialised differentiated form of cell membrane called me so some is the characteristic of prokaryotes. They are essentially the folding of cell membranes.
Eukaryotic cells have a nucleus enclosed within a nuclear envelope. Eukaryotic cells typically contain other membrane-bound organelles such as mitochondria, golgi apparatus , chloroplasts, vacuole, lysosomes, endoplasmic reticulum, ribosome etc
Similarities between the structure of prokaryotic and eukaryotic cell
1. The membrane of the cell
A lipid bilayer is an organisation of phospholipids and proteins found in both eukaryotic and prokaryotic cells that serve as a selective barrier between the cell’s internal and exterior environments.
2. Information on Genetics
Both eukaryotic and prokaryotic species store genetic information in Deoxyribonucleic Acid (DNA). Creating RNA through transcription and subsequently translating it into proteins requires this genetic material to govern and instruct cell function.
3. Ribosomes
Ribosomes aid in the translation of RNA and the production of protein, both of which are necessary for the survival of eukaryotic and prokaryotic cells.
4. Cytoplasm
The cytoplasm, of which cytosol is the principal component, is the medium in which the cell’s biological events take place.
The cytoplasm in eukaryotic cells includes anything between the plasma membrane as well as the nuclear envelope, including organelles; the nucleoplasm refers to the material within the nucleus. The cytoplasm, which includes the cytoskeleton and genetic material in prokaryotes, includes everything within the plasma membrane.
Differences between the structure of prokaryotic and eukaryotic cell
1. The most important distinction is that eukaryotes have “real” nuclei that house their DNA, whereas prokaryotes’ genetic material is not membrane-bound.
2. A prokaryotic cell’s diameter generally ranges between 0.1 and 5.0 micrometres.
Eukaryotic cells typically range from 10 to 100 micrometres in diametre.
3. The cell wall is present in prokaryotic cells and is exceedingly complex, while eukaryotic cells have cell walls quite rarely and if they do, they are chemically simple.
4. In prokaryotic cells, the true nucleus is absent, but a nucleotide is discovered in the central part of the cell, whereas, in eukaryotic cells, the actual nucleus is present.
5. In prokaryotic cells, DNA is structured in a circular shape; in eukaryotic cells, DNA is arranged in a linear shape.
6. The cytoplasm is found in prokaryotic cells, although it is absent from most cell organelles. It comprises both cytoplasm and organelles in eukaryotic cells and both are present.
7. Ribosomes are present in prokaryotic cells, but they are 70S (large unit 50s and small unit 30S) , whereas ribosomes are found in eukaryotic cells, but they are 80S(large unit 60S and small unit 40S).
8. Only asexual reproduction occurs in prokaryotic cells. Eukaryotic cells can reproduce both sexually and asexually.
9. The flagella of prokaryotic and eukaryotic cells differ in eukaryotes having a microtubule structure and being linked to the cell membrane through the basal body, whereas prokaryotes have flagella that are positioned outside of the plasma membrane.
The movement and structure of prokaryotic and eukaryotic flagella differ, with eukaryotes having a microtubule structure and being linked to the cell membrane through the basal body, whereas prokaryotes have flagella that are positioned outside of the plasma membrane.
The microtubular organisation and type of movement of prokaryotic and eukaryotic flagella differ. The organisation in eukaryotes is (9 + 2) and specialised, whereas the arrangement in prokaryotes is (9 + 0) and simple.
Conclusion
Prokaryotes are single-celled creatures that belong to the Bacteria and Archaea domains. A eukaryotic cell has a plasma membrane, cytoplasm and ribosomes, just like a prokaryotic cell, but it is normally bigger, has a genuine nucleus and additional membrane-bound organelles that allow for functional compartmentalisation.