Identify the types of bacteria according to their shape

Bacteria are unicellular microorganisms living on the earth and its atmosphere.

They are prokaryotic cells with no defined nucleus.

They can live in any extreme climatic conditions and are omnipresent.

They grow in colonies and can live as saprophytes and also as parasites in humans, animals, and plants, causing many diseases.

Due to this, their identification is essential in disease diagnosis.

Identifying them is possible by color, shapes, and also colony characters.

However, we will see bacteria based on shapes here.

Identify the types of bacteria according to their shape

  1. Rod-Shaped
  2. Spherical shaped
  3. Comma-shaped
  4. Spiral
  5. Spore form
  6. Clusters and bunches.


These bacteria are rod-shaped, like a stick. These bacteria are called bacillus bacteria.

rod-shaped bacteria

Examples of these bacteria

  • Helicobacter pylori cause gastric acidity.
  • Mycobacterium tuberculosis which causes tuberculosis.
  • Escherichia coli

Spherical bacteria

These bacteria are spherical in shape. They can exist as a single form or as a bunch of two, four, or more membered.

spherical bacteria

They are oval, circular, or spherical in shape.

Examples of bacteria with spherical shapes include

  1. Neisseria gonorrhea
  2. Meningococci bacteria
  3. Streptococci bacteria
  4. Staphylococci bacteria
  5. Micrococci
  6. Pneumococci bacteria


These bacteria are comma-shaped or hair-like.

comma-shaped bacteria

The best example of this type of bacteria is cholera-causing vibrio cholera bacteria.


These bacteria are long and spiral in shape. They are spring-like with a slight coil structure.

spiral shaped bacteria

Examples of this bacterial shape are syphilis bacteria that causes infection to the genitals in both males and females.

Spore form

These are bacteria that are formed into a protective form.

They are seen in cases of extreme conditions in which bacteria cannot survive.


Once the conditions are favorable, bacteria get off these spore forms.

All the types of bacteria transform into spores. It is also considered a type of bacterial reproduction.


These bacteria are a bunch of spherical bacteria.


Bacteria with different shapes are easy to identify once they are stained. They can be visible under the microscope in movable or immovable form.

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