Meaning of Bacteria

What is Bacteria:

The bacterium is a unicellular and prokaryotic microorganism, which means that it does not have a nucleus. Bacteria, along with protozoa, fungi, and algae, belong to the category of microorganismswhich are microscopic life forms.


The bacterium is essential for life on Earth and exists in the most diverse environments. It is the most abundant organism on our planet.

There are bacteria that coexist inside other organisms in symbiotic relationships called endosymbionts. The most common example is bacterial flora of our digestive tract that helps us process nutrients that we are not able to digest without their help.

According to their shape, bacteria are generally classified into: bacilli (walking stick), spirilla (spirals) or coconuts (spherical).

There are also harmful bacteria for our body. The Pathogenic bacteria are those that cause diseases in our body such as, for example, germs, typhoid fever, ulcers, salmonella, cholera and tuberculosis.

The father of microorganisms is considered to be the Dutch merchant Anthony van Leeuwenhoek (1632-1723), who first observed the first bacteria or prokaryotic cells with his microscope.

Characteristics of bacteria

Bacteria have the following characteristics:

  • They are prokaryotes: has no nucleus and are formed by a single chromosome.
  • They have a unique and circular DNAThey swim free in the cytoplasm.
  • They reproduce through binary fissions o cell division: the DNA divides and then its cytoplasm also divides to create two daughter cells.
  • It has a cell wall made of peptidoglycan: very resistant because it has a straight chain and is not branched.
  • They have different methods of metabolisms and habitats.
  • Some have cilia or flagella.
  • They belong to the Monera kingdom.
You may be interested:  Major and Minor Circulation