Microorganisms - Power Point - News

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Supporting education in Ethiopia
“Salam! My name is Sewnet.
Today we are going to learn
about Microorganisms. I will
be your guide as we look
around my village.”
Supporting education in Ethiopia
What is a Microorganism?
Microorganisms are very tiny living things. They are so small that you
need a microscope to see them.
Microorganisms are all around us, in the air, in our bodies and in water.
Some microorganisms are harmful to us, but others are helpful to us.
There are three types of microorganism:
• viruses
• bacteria
• fungi
Supporting education in Ethiopia
Harmful Microorganisms
Some microorganisms can harm us.
Bacteria and viruses, often called germs, can cause disease.
This is a type of bacteria called
‘Streptococcus’ which commonly
causes sore throats.
This is an example of a virus
which causes the common cold.
Supporting education in Ethiopia
Bacteria and viruses can also cause diarrhea and upset stomachs. They can
be easily transmitted if people do not wash their hands after going to the
toilet.
“At my school, many children
used to get sick because we had
nowhere to wash our hands
after using the toilet.
With the help of Link Ethiopia
and our partner school, we built
taps with clean water – now we
miss much less school!”
Supporting education in Ethiopia
Mold is a type of
microorganism that grows on
decaying food. It can make you
ill if you eat it.
“In my village, many homes do not have
electricity, so people cannot keep food
in fridges. They have to be careful to eat
food quickly before it goes moldy.”
“In order to preserve meat, we hang it
up to dry!”
Supporting education in Ethiopia
Useful Microorganisms
“In Ethiopia, our bread is called ‘Injera’. We
make it in a similar way to English bread. We
make dough from a crop called ‘teff’ mixed with
water. We then add a stale piece of injera to the
dough which contains yeast, a microorganism.”
“The yeast reacts with the dough to create
carbon dioxide, which causes the injera to
rise and gives it a light, pancakey texture.
Most of the bubbles of carbon dioxide
escape, giving the surface of the bread its
distinctive bubbles.”
Supporting education in Ethiopia
Most cheeses are made by
adding bacteria to milk. The
bacteria reacts with the sugar
in the milk to form lactic acid.
The acid causes the milk to
separate into liquid ‘whey’ and
solid ‘curds’ which can then be
turned into cheese.
“In Ethiopia, the most common
cheese is called ‘ayb’. It is similar
to feta cheese. We often eat it
mixed with cabbage or served
with a meat dish called ‘kitfo’.”
Supporting education in Ethiopia
Penicillin, a type of mold, is one of the most commonly used medicines. Penicillin
an ‘antibiotic’: it kills a lot of different bacteria and is very safe (it has few side
effects and a very high amount is needed to harm anyone). If you ever have a
chest or throat infection, your doctor might give you some medicine like penicillin
to help you get better.
Penicillin was discovered
accidentally, at St. Mary's
Hospital, in London, by Dr.
Alexander Fleming in 1928.
During World War II, many
soldiers’ lives were saved
by this new antibiotic,
which stopped wounds
from becoming infected.
Supporting education in Ethiopia
Waste breakdown is another useful function of bacteria. Have you ever been camping and
used a pit latrine or ‘long-drop’ toilet? These toilets are commonly used where there is no
sewer system. Waste collects in a deep pit, where it is broken down into compost by
bacteria.
“In Ethiopia, toilets such as this
one are most common as most
villages do not have sewer
systems. “
“They can be a really useful
source of compost to grow fruit
trees and vegetables!”
Supporting education in Ethiopia
“Thanks for looking around
with me. I hope you have
enjoyed finding out about
microorganisms and
Ethiopia.
Now see if you can answer
the microorganism quiz! ”
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