Aliya Hussain
Unit 17.1: classification of microorganisms
Content page
Page
P1 1-12
M1 12-15
P2&P3 16-17
M2 & D1 18-21
Bibliography 22-23
1
,Aliya Hussain
Classification of organisms
Microorganisms can be classified on the basis of cell structure, cellular metabolism,
or on differences in cell components such as DNA, fatty acids, pigments, antigens,
and quinones. All living things are classified into 3 domains; Archaea, Bacteria and
Eukarya. Within Eukarya there are different kingdoms; protists, fungi, plants and
animals.
Figure 1
Why it is important to classify microorganisms
Classification of microorganisms is important at it helps in the identification of living
organisms as well as in understanding the diversity of living organisms. Classification
is also important as it allows scientists to group together similar microorganisms and
help them look at how they might have evolved over time. Classification also helps in
identifying the causes of diseases which is extremely important.
Figure 2
This diagram is based on the comparisons between the microorganisms. For
example, similar structural or physical characteristics between the microorganisms.
2
, Aliya Hussain
The importance for microbial classification for medicine and industry
In medicine:
Identification of causes of diseases
It is important to classify microorganisms as it helps to identify the cause of a
disease. Infectious diseases commonly spread through the direct transfer of bacteria,
viruses, fungi or parasites or other germs from one person to another. Classification
allows us to easily identify if the disease is caused by bacteria, virus, fungi, or
parasite. Clinical tests on blood, urine and faeces can be carried out in order to
identify the cause of disease. These tests are carried out as bacteria, viruses and
fungi can show up in body fluids.
Blood test- blood tests help reveal eukaryotic infections, such as malaria, which is
caused by Plasmodium, a eukaryotic organism transmitted through mosquito bites.
serological blood tests can be carried out in order identify the presence or level of
specific antibodies in the blood. These specific antibodies help the body fight against
viral infections for example the Rotavirus. Also, blood culture test can be carried out
to identify the bacteria or fungi in the blood. Blood samples are taken then put onto
a plate of medical jelly (agar) and kept in a warm environment for a few days to
identify what microorganisms grow. The agar place can then be used to work out
which medicines get rid of the bacteria or fungi.
Urine test- Urine tests can help identify which microorganism is the cause of a kidney
or bladder infection. The urine sample is also wiped on the surface of an agar plate
and kept in a warm environment to grow and identify what sort of bacteria or fungi is
present, how many there are, and which medicines will work against it.
Faeces test- For a test on faeces the faeces are wiped on the surface of an agar plate
and incubated to grow the bacteria or fungi in it so they can later be identified.
However, the faeces test can also be done by placing a tiny amount of it on a glass
slide and examining it under a microscope to look for specific microorganisms.
Faeces can also go through another test called the polymerase chain reaction which
detects genetic material that can sometimes show the presence of viruses.
Specialised growth media- growth medium is a liquid or gel that contains nutrients
that can support the growth of microorganisms. Growth media is essential for
diagnosing infectious diseases, obtaining antigens, developing serological assays for
vaccines, genetic studies, and identification of microbial species. There are two
commonly used physical forms of growth media: liquid media and solid growth
media. A liquid medium is called a broth. Agar is used to prepare solid media in labs.
3
Unit 17.1: classification of microorganisms
Content page
Page
P1 1-12
M1 12-15
P2&P3 16-17
M2 & D1 18-21
Bibliography 22-23
1
,Aliya Hussain
Classification of organisms
Microorganisms can be classified on the basis of cell structure, cellular metabolism,
or on differences in cell components such as DNA, fatty acids, pigments, antigens,
and quinones. All living things are classified into 3 domains; Archaea, Bacteria and
Eukarya. Within Eukarya there are different kingdoms; protists, fungi, plants and
animals.
Figure 1
Why it is important to classify microorganisms
Classification of microorganisms is important at it helps in the identification of living
organisms as well as in understanding the diversity of living organisms. Classification
is also important as it allows scientists to group together similar microorganisms and
help them look at how they might have evolved over time. Classification also helps in
identifying the causes of diseases which is extremely important.
Figure 2
This diagram is based on the comparisons between the microorganisms. For
example, similar structural or physical characteristics between the microorganisms.
2
, Aliya Hussain
The importance for microbial classification for medicine and industry
In medicine:
Identification of causes of diseases
It is important to classify microorganisms as it helps to identify the cause of a
disease. Infectious diseases commonly spread through the direct transfer of bacteria,
viruses, fungi or parasites or other germs from one person to another. Classification
allows us to easily identify if the disease is caused by bacteria, virus, fungi, or
parasite. Clinical tests on blood, urine and faeces can be carried out in order to
identify the cause of disease. These tests are carried out as bacteria, viruses and
fungi can show up in body fluids.
Blood test- blood tests help reveal eukaryotic infections, such as malaria, which is
caused by Plasmodium, a eukaryotic organism transmitted through mosquito bites.
serological blood tests can be carried out in order identify the presence or level of
specific antibodies in the blood. These specific antibodies help the body fight against
viral infections for example the Rotavirus. Also, blood culture test can be carried out
to identify the bacteria or fungi in the blood. Blood samples are taken then put onto
a plate of medical jelly (agar) and kept in a warm environment for a few days to
identify what microorganisms grow. The agar place can then be used to work out
which medicines get rid of the bacteria or fungi.
Urine test- Urine tests can help identify which microorganism is the cause of a kidney
or bladder infection. The urine sample is also wiped on the surface of an agar plate
and kept in a warm environment to grow and identify what sort of bacteria or fungi is
present, how many there are, and which medicines will work against it.
Faeces test- For a test on faeces the faeces are wiped on the surface of an agar plate
and incubated to grow the bacteria or fungi in it so they can later be identified.
However, the faeces test can also be done by placing a tiny amount of it on a glass
slide and examining it under a microscope to look for specific microorganisms.
Faeces can also go through another test called the polymerase chain reaction which
detects genetic material that can sometimes show the presence of viruses.
Specialised growth media- growth medium is a liquid or gel that contains nutrients
that can support the growth of microorganisms. Growth media is essential for
diagnosing infectious diseases, obtaining antigens, developing serological assays for
vaccines, genetic studies, and identification of microbial species. There are two
commonly used physical forms of growth media: liquid media and solid growth
media. A liquid medium is called a broth. Agar is used to prepare solid media in labs.
3
