Biology

Prokaryotic and Eukaryotic

The difference between prokaryotic and eukaryotic cells is that eukaryotic organisms have a nucleus surrounded by a membrane, whereas prokaryotes do not. Difference between prokaryotic and Eukaryotic cellsIn prokaryotes, DNA is found in a region of the cytoplasm, called the nucleoid, unlike in the eukaryotic cell, where genetic information is found in the nucleus.

The cell is the basic and indispensable unit present in every living being. It is the smallest element alive. The three vital functions of every organism (nutrition, reproduction, relationship) are carried out by all the cells that compose it.

Depending on their structure, cells can be:
  • Eukaryotic cells. They have a defined cell nucleus covered by a membrane. Within this membrane are the chromosomes that store the body’s genetic information. All organisms of the animal kingdom, plant kingdom, fungi, and protists kingdom are formed by eukaryotic cells. For example the protist Plasmodium, the animal cells present in a locust, the plant cells present in a jacaranda.
  • Prokaryotic cells. They do not have a defined nucleus and lack a cell membrane. Its genetic material is scattered in the cytoplasm. The bacteria and archaea are the two types of organisms with prokaryotic cells. For example methanogenic archaea or pseudomonas bacteria.
  • It can serve you: Human cells and their functions

Characteristics of eukaryotic cells

  • They integrate kingdoms of multicellular beings (formed by several cells) and unicellular (formed by a single cell). The cells of each type vary in structure and characteristics. They are much larger in size than prokaryotic cells.
  • They are aerobic, they need oxygen to live.
  • They reproduce through mitosis (two genetically identical daughter cells originate from a stem cell) and meiosis (four different cells arise from a diploid cell).
  • They have organelles, structures within the cytoplasm, that fulfill various functions. For example: in a plant cell, the chloroplast organelle performs the function of photosynthesis. Not all cells have all organelles.
  • They have ribosomes (organelles that synthesize proteins) more complex than those of prokaryotic cells.
  • The plant cell has a cell wall made of cellulose. The animal cell has no cell wall.

Characteristics of prokaryotic cells

  • They are only found in single-celled organisms. They have a smaller structure and are less complex than eukaryotic cells.
  • The genetic material is found in the cytoplasm, in an irregular area called the nucleoid.
  • They can be aerobic or anaerobic (they don’t need oxygen to live).
  • They reproduce asexually or parasexually.
  • Nutrition can be autotrophic (photosynthesis or chemosynthesis) or heterotrophic (it feeds on another organism that it parasites)
  • They have cytoplasm, plasma membrane, cell wall, nucleoid, and ribosomes.

Examples of eukaryotic cells

  1. Neuron
  2. Euglena
  3. Amoeba
  4. Red blood cell
  5. Paramecium

Examples of prokaryotic cells

  1.  Eubacteria
  2.  Spirochetes
  3.  Planktonic
  4. Blue-green algae
  5. Methanogens

Similarities Between Prokaryotic and Eukaryotic Cells

While prokaryotic and eukaryotic cells are different in many ways, they also exhibit certain similarities. Both contain genetic material, that is, DNA. They have a cell membrane that covers them. Their basic chemical structures are similar, both being made up of carbohydrates, proteins, nucleic acid, minerals, fats, and vitamins.

Both prokaryotic and eukaryotic cells contain ribosomes, which make proteins. The two types of cells regulate the flow of nutrients and waste matter into and out of cells. They also reproduce, although in different ways. They need the energy to survive, they contain cytoplasm inside cells and a cytoskeleton. Both classes of cells have a lipid bilayer, known as the plasma membrane, that forms the boundary between the inner and outer sides of the cell.

Difference between Prokaryotes and Eukaryotes

There are also certain differences between prokaryotic cells and eukaryotic cells. Scientists believe that eukaryotic cells evolved from prokaryotic cells.

But what are these differences? In the following lines, we explain them to you.

1. Core

While eukaryotic cells have a well-defined nucleus, prokaryotes do not. Genetic information is stored within the nucleus of eukaryotes.

2. Origin

It is estimated that prokaryotic cells have their origin around 3.7 billion years, whereas eukaryotic cells 2 billion years.

3. Size

Prokaryotic cells are smaller: 0.1–5.0 µm in diameter. The largest eukaryotes: 10-100µm in diameter.

4. Cell organization

Prokaryotic cells are usually unicellular, whereas eukaryotic cells are multicellular.

5. Genetic material

The genetic material of eukaryotes is stored in the nucleus; however, in the case of prokaryotic cells, it is dispersed throughout the cytoplasm. The DNA of prokaryotic cells does not associate with histones.

6. Composition of the plasma membrane

In eukaryotic cells, plasma membranes contain sterols . In the case of prokaryotic cells, only in

mycoplasmas.

7. Form of genetic material

In prokaryotic cells, DNA is circular. Now, when it comes to eukaryotic cells, DNA is linear and, as mentioned above, it is associated with histone proteins.

8. Number of chromosomes

Prokaryotic cells have only one chromosome. However, eukaryotic cells have multiple chromosomes .

9. Plasma membrane

In prokaryotic cells the plasma membrane is composed of peptidoglycan or murein. In the case of eukaryotes, it is made up of phospholipids.

10. Organizers

Prokaryotic cells have an interior matrix with nonmembranous organelles . Prokaryotic cells present in the cytoplasm membranous organelles (for example, Golgi apparatus).

11. Reproduction

Reproduction in prokaryotic cells occurs by asexual reproduction, by binary fission. In contrast, in eukaryotic cells, reproduction occurs by  mitosis and meiosis .

12. Living organisms

Prokaryotic cells are bacteria , while prokaryotic cells are part of animals, plants, fungi, protozoa, and algae.

  • More examples in: Multicellular organisms

 

Related Articles

Leave a Reply

Your email address will not be published.

Back to top button