While he was not the first to argue that infectious diseases were caused by germs, his work was of paramount importance in demonstrating the relevance of germ theory to infectious diseas
Trang 1A World of Mystery
English Toolkit 1 - Natural Sciences
The scientific contributions of Louis Pasteur (1822-1895), French chemist and microbiologist, were among the most valuable in the history
of Science While he was not the first to argue that infectious diseases were caused by germs, his work was
of paramount importance in demonstrating the
relevance of germ theory to infectious disease,
surgery, hospital management, agriculture and
industry
In the early 1860s, he began working on
fermentation Studies of the industrial fermentation
of beet juice led him to the hypothesis that
ferments Pasteur demonstrated that yeast was a
microorganism that converts sugar into alcohol In
History of Lactic Acid Fermentation, Pasteur stated
that certain kinds of fermentation were caused
by the activities of specific microscopic living
organisms and that many diseases were also caused
by particular germs Thus, he laid the foundation
for the germ theory of disease
These studies had great economic significance as
well, because they provided a means of gaining
some control over the production of wine, beer and
vinegar
He further showed that spoilage of perishable substances can be averted by destroying microorganisms to prevent contamination, resulting
in the process of pasteurisation
Pasteur demonstrated that wine and beer could be preserved by heating above 57.2º C (135º F) for a few minutes
Pasteurisation of milk, widely practised in several countries, requires temperatures of about 63º C (145º F) for 30 minutes or, alternatively, heating to
a higher temperature, 72º C (162º F) for 15 seconds
An accidental discovery
The Hungarian physician Ignaz P Semmelweis (1818-1865) greatly reduced the incidence of puerperal fever through his pioneering work in antiseptic techniques
Realising that physicians in certain wards of Vienna hospitals carried the disease from the autopsy room and transmitted it to women in the maternity ward,
Semmelweis ordered all physicians in his service to wash their hands thoroughly before examining patients
Semmelweis himself died of puerperal fever before his views were widely accepted
Discoveries: Two Brilliant Minds
Activities
1 State if the following sentences are true (T) or false (F).
a According to Pasteur’s studies, fermentation depends on living germs
b Wine and beer can’t be preserved by heating above 57.2º C
c Specific germs cause many diseases
d Pasteur was the first to argue that infectious diseases were caused by germs
e Semmelweis made puerperal fever disappear completely through his antiseptic
techniques
Adapted from: http://gi.grolier.com/encyclopedia
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English Toolkit 1 - Natural Sciences
2 Read the text again and find synonyms for these words
4 Write about Pasteur using
the information provided
in activity 3.
3 Complete this information about Pasteur.
5 Find out information about three different personalities who made
important discoveries and / or were awarded a Nobel Prize in your
country Write a paragraph about one of them Include a photo of the
personality if you want.
f The disease was spread through examining patients in the maternity ward
g Physicians had to wash their hands carefully before examining patients
h Semmelweis died of puerperal fever being well known for his work in antiseptic
techniques
a doctor:
b temperature:
c investigation:
d methods:
e illness:
f instructed:
g thoroughly:
h ideas:
Name:
Born in:
Died:
Nationality:
Occupation:
Theory:
Early 1860s:
Demonstration:
Discovery: