Unicellular organisms have only one cell.
Unicellular is the adjective used to describe organisms that have a single cell . Cells, for their part, are the fundamental components of living beings, which can reproduce independently.
Before moving forward, it is important to know the etymological origin of the term. In this sense, it must be stated that it derives from Latin, since it is the result of the sum of two words from that language: unus , which can be translated as "one" , and the noun cellula , which is equivalent to "cell" .
It is important to keep in mind that all organisms are, in their beginnings, unicellular, since they come from a zygote . Over time , beings differentiate between those that maintain a single cell ( unicellular ) and those that are made up of multiple cells that have different functions ( multicellular ). It should be noted that most organisms are unicellular.
Advantages of unicellular organisms
It is considered that being multicellular is something positive since beings of this type, among other things, have more possibilities, functionalities and organs to be able to adapt in the best way to the changes that appear in their lives.
By having only one cell, unicellular organisms are simpler than multicellular organisms. In the case of multicellular beings, cells specialize in different functions and combine to form tissues , which in turn are linked into organs that act in systems . This makes the most complex species, such as humans , multicellular.
Bacteria are unicellular.
Different types
Unicellular organisms can be prokaryotes or eukaryotes . Prokaryotic organisms, also called prokaryotes , are characterized by lacking a cell nucleus: in this way, the DNA is free inside the cytoplasm .
Eukaryotic or eukaryotic organisms, on the other hand, have a nucleus that contains DNA .
Study of unicellular beings
There are different theories and in-depth studies on cellular organisms and precisely one of the best known is the one carried out by the botanist and ecologist Robert Hardind Whittaker ( 1920 - 1980 ), who determined that there were five kingdoms to classify them. Specifically, he also explained that unicellular beings were grouped into three of these kingdoms: the protists , the moneras , which is where the prokaryotes are grouped, and some fungi .
An example of a prokaryotic-type unicellular organism is bacteria . Escherichia coli , Helicobacter pylori and Leptospira are some of the beings that make up this group. Regarding single-celled eukaryotic organisms, we can mention protozoa , such as amoebas and paramecium .
derogatory use of the term
It must be stated that there are those who even use the term in question as an insult.
Thus, they may tell another person that they are “single-celled” as a way of making it clear that they are someone who is basic in their behavior and that they are not capable of thinking adequately, that they do not have culture or that they lack knowledge.