Meaning of prokaryotic cell
What is prokaryotic cell:
The prokaryotic cell is characterized by not having a cell nucleus, therefore its ribosomes are smaller and its genetic material simpler.
Prokaryotic cells are mostly bacteria and are known as one of the first living organisms.
The word prokaryote is etymologically composed of the prefix pro- which means "before" and karyo which refers to "nucleus", therefore, the prokaryotic cell is considered anterior to the cell having a cell nucleus or Eurkaryotic cell.
The prokaryotic kingdom, prokaryotic cell organisms, is also known as the monera kingdom, composed mostly of bacteria and archaea.
Structure of a prokaryotic cell
The prokaryotic cell is the most basic unit of life and is made up of only one part.
Having no nucleus, the prokaryotic cell is a single space called the cytoplasm, which is filled with cytosol, a gelatinous substance. Suspended in the cytosol is the nucleoid, the structure where its DNA is found, also known as the circular chromosome.
Along with the giant loop of genetic information swim the ribosomes that have the function of synthesizing the proteins that will carry out all the vital functions necessary for life.
All of this is separated from its external environment by a cell membrane and a cell wall.
The cell membrane, also known as the plasma membrane, is a semipermeable phospholipid bilayer that maintains the integrity of the cell. this membrane is present in all cells, both prokaryotic and eukaryotic.
The cell wall is made of peptidoglycan (carbohydrates and small proteins) that maintains the shape of the cell and prevents dehydration.
Some prokaryotic beings, mostly bacteria, have an additional layer of carbohydrates adherent to the surfaces of their environment known as the cell capsule.
Some bacteria also have flagella, cilia or pilis, filaments or structures that help the cell to move or adhere to the environment in which it is found.
It may interest you Parts of the cell.
Prokaryotic and eukaryotic cell
The prokaryotic cell is considered the ancestor of the eukaryotic, therefore they share several characteristics. Both have a plasma membrane, cytoplasm, cytosol, DNA, and ribosomes.
The eukaryotic cell differs from the prokaryotic by having a nucleus, where there is a more complex DNA, larger ribosomes and a clear division with the rest of the cell due to the presence of a nuclear wall.
The prokaryotic cell has a rigid cell wall like that of plant cells, cells of the fungi kingdom, and algae. Prokaryotic cells were discovered in 1920 by the Swiss-French biologist Édouard Chatton (1883-1947). When noticing the existence of cells without a defined nucleus, he calls them prokaryotes and those with a eukaryotic nucleus.
In 1938, the American biologist Herbert Copeland (1902-1968) classified prokaryotic cells in the fifth kingdom of nature: the monera kingdom or prokaryotic kingdom.
The prokaryotic kingdom is mostly bacteria, first observed by the Dutch merchant Anthony van Leeuwenhoek (1632-1723), later known as the "father of microorganisms".
Thanks to the discovery of microorganisms and the postulates of the cell theory in 1830, the beginning towards the acceptance of the theory of biogenesis ("life can only come from another pre-existing life"), validated only in 1887, begins.