7/28/2019 Bacterial Classification Based on Shapes

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Bacterial Classification Based on Shapes

As already mentioned, before the advent of

DNA sequencing, bacteria were classified based

on their shapes and biochemical properties.

Most of the bacteria belong to three main

shapes:

Rod-shaped bacteria are called bacilli - e.g.

E.Coli and Salmonella

Spherical-shaped bacteria are called cocci - e.g.

Staphylococcus and Streptococcus

Spiral-shaped bacteria are called spirilla - e.g.

Treponema and Borellia

There are three basic classifications for colony

morphology. And each classification hasdifferent ones. Here they are:

Shape of the Colony- this is broken up into

*round

*irregular

*filamentous

*rhizoid

The type of Edge on the colony-

*undulate

*lobate

*rounded

The elevation of the colony-

*raised

*flat

*convex

*umbonate

Here is a list of 5 infectious diseases that arecaused by bacteria.

1. Cholera

Cholera is caused by the bacterium Vibrio

cholerae which contaminates water and food

usually seafood. It can cause diarrhea and water

loss.

2. Meningitis

Meningitis can be caused either by a virus or

bacteria. Many different types of bacteria can

cause meningitis but the majority of cases of

bacterial meningitis are the meningococcal or

the pneumococcal. The bacteria cannot live

outside the human body. It thrives on the back

of the nose and throat, or in the upper

respiratory tract. As such, this disease is spread

through coughing or sneezing or kissing.

3. Tetanus

Tetanus is caused by a toxin produced by the

bacterium Clostridium tetani. This disease

cannot be spread from person to person but the

bacterium is present in the soil, in the intestines

and feces of household and farm animals aswell as human excretion. It is a dangerous

disease as it attacks the nervous system and

causes paralysis which can lead to death but

this disease can be easily prevented through

vaccination.

4. Tuberculosis

Tuberculosis is caused by the bacterium

Mycobacterium tuberculosis which is spread

through the air. This is a

highly infectious disease which causes difficulty

in breathing as the bacteria infect the lungs.5. Whoopping cough (pertussis)

Whooping cough is caused by the bacterium

Bordatella pertusis which is spread through the

air. It can cause severe coughing caused by an

infection of the windpipe (trachea).

The above infectious diseases are now not as

fatal as they used to be with new treatments

found and many advances in the health field.

However, if proper treatment and vaccination

are not given, these infectious diseases cancause death.