The document discusses microorganisms and the diseases they can cause. It describes the three main types of microbes - viruses, bacteria, and protozoa - and examples of diseases caused by each, such as HIV, tetanus, and malaria. The document also covers how environmental changes can disturb the balance between microbes and other species, allowing microbes to multiply rapidly and cause disease. It discusses the history of linking microbes to specific diseases through the work of scientists like Leeuwenhoek, Pasteur, and Koch. Modern research and treatments like vaccines and antibiotics are also mentioned.

1. Microorganisms
and Deadly Diseases
By Karishma Deegan

2. Contents page
It’s a small world: different types of microbes.
Virus: living or non-living.
Bacteria: friend or foe.
Powerful protozoa.
Fungi : fabulous, but not always.
Microbes and disease, making the link.
Research and development: eradicating
diseases.
 Quiz.

3. Micro-organisms & Deadly diseases
Micro-organisms or microbes – are tiny organisms
living in the environment all around us ( air water soil
and living things) that cannot be seen with the naked
eye hence the word micro (microscopic ) as can be
seen only under a microscope. Although most micro-
organisms are essential for our survival a small
percent enter our bodies to cause infectious diseases.
Environment and economic conditions play a role in
the spread of diseases.
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4. Environment Change and Spread of Diseases
In the environment microbes interact with humans and
animals in an unique way if the environment is disturbed by
drought, tsunami etc the balance between the microbes and
other species gets disturbed this leads to the microbes to
multiply rapidly and thus cause diseases. Because microbes
can grow fast they can adapt to different environmental
changes quickly. This can be stopped if man is more careful
and looks after and protects his environment .
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5. It’s a small world: different types of
microbes.
• There are three major groups of microbes:
viruses, bacteria and protozoa. Within each
group are numerous species that differ in
shape, size, and structure, as well as food
intake and reproductive processes. Some
larger organisms, such as flukes and
worms, and fungi, can also cause infectious
diseases
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6. Virus : living or non living
• Virus : They are the smallest microbe that do not
have a cell and therefore cannot live on their own.
They live inside the host cell of living things and
often cause the host cell to die, virus are thus the
most dangerous microbes to human beings. Some
examples of diseases caused by viruses include
flu, hepatitis B, and AIDS (caused by a virus called
HIV)
HIV- Human Immunodeficiency Virus Poxviridae- Small Pox Virus 4

7. Acquired immune deficiency syndrome
Human immunodeficiency virus causes AIDS.
It attacks the white blood cells in the our body
and causes it to die. The white blood cells are
the cells that fight diseases and gives us
immunity by causing those cells to die AIDS
completely weakens the human and they
eventually die there is no cure for AIDS yet.
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8. Bacteria: Friend or foe
• Bacteria - They live almost everywhere: in the soil and
water, in plants and animals. They can adapt to extremely
harsh environments, such as hot springs and tundra. If
conditions turn unfavorable, some bacteria can remain
dormant until things improve. They take the form of
spheres, rods, or spirals, bacteria consist of a single cell
• There are thousand species of Bacteria C.Tetani -
only some of them cause diseases for CausesTetanus
example Tetanus , TB, Dysentery etc . Some
bacteria are indeed helpful like bacteria that makes yogurt
helps with digestion. Anti-Biotics help to cure diseases that
are caused by bacteria.
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9. Powerful Protozoa
Protozoa – they are also single celled
micro organisms like bacteria. There
are many species of protozoa and
they are in various shapes and sizes.
Most protozoa do not cause diseases Malaria-infecting a red
blood cell.
but some are harmful such as the
protozoa that causes Malaria. Malaria
infects 300 million people each year 2
million children and adults die every
year and 2 children die of malaria
every minute.
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10. Fungi- Fabulous but not always.
Fungus : They are like plants but unlike plants
they cannot make their own food and thus
either live in dead plants and animals or live
in cells of living things. Fungus are like
mushrooms, yeast, and mould. Fungus can
Athletes foot cause diseases but can also be helpful to man
for example a kind of fungus is used to make
the PENICILLIN drug that Alexander Fleming
discovered by accident in1928 - a powerful
antibiotic that kills a particular kind of bacteria
in our body. Yeast helps to make dough rise.
Fungus can also causes diseases like athletes
foot that grow in between our toes.
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11. Epidemic or pandemic?
Epidemics occur when an infectious disease spreads beyond a
local population, lasting longer and reaching people in a wider
geographical area. When that disease reaches worldwide
proportions, it's considered a pandemic. Several factors
determine whether an outbreak will explode into an epidemic
or pandemic: the ease with which a microbe moves from
person to person, and the behavior of individuals and
societies. The Aztecs were devastated by
small pox which they had never encount-
ered before the Spanish crusader's came
to South America in the 16th century.
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12. MICROBES AND DISEASE: MAKING THE LINK
Leevanhoek-Pasteur-Koch
• A 17th century Dutch Leeuwenhoek's
merchant named Antoni van illustration of Planaria, a
Leeuwenhoek was the first type of flatworm—one of
person to see a living the organisms he found
microbe. It was 200 years in water.
before researchers realized
that some of these microbes
could cause disease. Louis
Pasteur, who was studying Robert Koch (left)
the microbes that cause wine and Louis Pasteur
to ferment, reasoned that (right) both
microbes might also be promoted the idea
responsible for illnesses. By that microbes cause
the 1880s, the German disease, debunking
scientist Robert Koch the old theory that
identified the bacteria that disease arose by
cause anthrax, cholera, and spontaneous
tuberculosis. generation.
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13. Research and development- Eradicating Diseases
For thousands of years, people have
recognized the symptoms of infectious
diseases, and every culture has found
ways of healing the ill. In the
1600s, however, a revolutionary piece of
equipment was invented—the
microscope. By revealing the previously
unseen world of microbes, the microscope
opened the way to new approaches to
understanding disease. Due to a lot or Jonas Salk administers a polio
research treatment and vaccination has vaccine, which he developed in the
been found for a lot of deadly diseases like 1950s.
Polio, Small pox Tetanus, Cholera etc. Laboratory
Research is going on in many countries of workers MUST
the world to rid the people of diseases for wear protective
which solutions have not yet been found
clothing to
for example AIDS. An electron microscope
can magnify an object 200,000 to 400,000 prevent
times its actual size, making visible the infection with
tiniest viruses and the inner details of microbes under
other organisms, such as bacteria. study.
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14. Quiz
• 1) What type of microbe causes tetanus?
a) Bacteria
b) Fungus
c) Virus
2) How does disease spread?
a) By sitting next to each other.
b) By sneezing and coughing.
c) By taking your vaccinations on time.
3) What is a pandemic?
a) When more than one village has the same disease.
b) When the disease spreads from one country to the other.
c) When Malaria kills more than 2 children every minute.
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15. QUIZ
3) What is used to make Penicillin?
a) Bacteria
b) Virus
c) Fungus
4) Which is the most dangerous microbe to
humans?
a) Bacteria
b) Virus
c) Fungus
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