How did scientists finally discover the
causes of disease?
Early stages
By the end of the lesson you ...
 must be able to describe how people
linked germs and disease.
 should be able to name factors which
helped each step and give examples.
 Could explain how factors enabled these
discoveries and explain links between
them.
1826 Improved
microscope by
Joseph Jackson
Lister.
Disproved theory of
spontaneous
generation
Brewery work
Louis Pasteur,
Scientist who
published
Germ Theory in
1861
1875 Doctor Robert Koch
began to investigate
whether specific bacteria
caused specific diseases
Pages 24 - 25
 On your mind map add details of the work and discoveries
of Pasteur and Robert Koch. Ensure you include any further
dates.
 In a different colour pen write in where the following factors
helped their work.
 Chance
 Technology
 Industry
 Science
So bad, it’s good?
http://www.youtube.com/watch?v=_Iuw6KCx-hA
Page 25
 Complete activities.
Germ theory –
remember it!
1861
Scientists now knew that
germs cause disease
There were two ways this could
be developed to benefit health.
What were they?
Prevention
Cure
The Development of Germ Theory
For centuries people had made a common-sense link between
and
. In the late 1600s a Dutch clockmaker called
some of the earliest
made
. With these he saw
which he called
.
Technical advances as part of the
improved the quality of glass, and a scientist called
developed a better
which showed clearer and more detailed
images.
One theory about these organisms was that decaying matter
them. This was called
. In
an alternative theory was published by
. He
believed that decay was caused by
in the
.
Worksheet 53
What the step involved
Discovering micro-organisms
Improved microscopes
Pasteur’s germ theory
Germ theory vs. spontaneous
generation (and it wins!)
Linking micro-organisms to
disease.
Proving the link between
bacteria and human disease.
Why this step was so
important
The important factors which
helped scientists make the
step.
What the step involved
Why this step was so
important
The important factors
which helped scientists
make the step.
Discovering microorganisms
Improved technology
Improved microscopes
Improved technology
Science
Pasteur’s germ theory
Links with industry.
Science/ Individual genius
Germ theory vs.
spontaneous generation
(and it wins!)
Competition
Scientific method
Linking micro-organisms to
disease.
Individual genius.
Links with industry
Proving the link between
bacteria and human
disease.
Communication.
Scientific method.
What the step involved
Why this step was so
important
The important factors
which helped scientists
make the step.
Discovering microorganisms
Knew they existed (but not
what they were).
Improved technology
Improved microscopes
Enabled closer
examination of microorganisms.
Improved technology
Science
Pasteur’s germ theory
Finds that microorganisms can have an
effect on substances.
Links with industry.
Science/ Individual genius
Germ theory vs.
spontaneous generation
(and it wins!)
Moved away from a
misleading idea.
Competition
Scientific method
Linking micro-organisms to Suggests the connection
disease.
for the first time.
Individual genius.
Links with industry
Proving the link between
bacteria and human
disease.
Communication.
Scientific method.
One of main causes of
disease has been
identified.