Teacher’s notes
Researching bacterial cultures and antibiotics
Integrated strands
Science concept
Some fungi secrete chemicals that inhibit the growth and reproduction of certain bacteria.
Nature of Science Theme
- Scientific explanations may involve creative insights…
- New lines of research occur when a scientist views an existing pattern in a new and creative way.
DSSA Investigation Focus
- Students’ investigations may have unexpected results…
- Discussing with students how they might deal with unexpected results in their experiments may provide an opportunity for further enquiry or clarification.
Rationale
While researching the work of Alexander Fleming (1928), students will
discuss the role of creativity and insight in scientific discovery.
This can be compared with their own experience of experiments that give
unexpected results.
Activity
Curriculum level 6
Living world Topic
Health
Type of investigation
Researching
What you need
- Bacterial agar plates that have been inoculated, contaminated with
fungi, and incubated. Ministry of Education safety guidelines should
be followed (see activity resources below).
- Alternatively, use photographs of bacterial cultures on agar plates,
one with an antibiotic fungal colony.
- Literature on the work of Alexander Fleming on antibiotics. Approach
the National Library, Advice and Services through your school library.
Inform them of the required reading level.
Note: Supporting activity resources are provided
below.
Focus
- What are antibiotics? When are they used and how are they made?
- What prompted Fleming to investigate these chemical substances in
1928?
- What is our usual response when an experiment ‘goes wrong’,
that is to say, gives unexpected results?
Exploration
- In groups, give students access to the agar cultures (or photographs).
If you give them sealed bacterial plates, provide the appropriate safety
instructions.
- Discuss with them what is supposed to happen when we make pure cultures
of bacteria and have them share their ideas about what the problem might
be with the batch in front of them (or in the photographs).
- In groups, have them discuss what they would do if this were their
own experiment and report back to the class.
- Introduce the name and a very brief biography of Alexander Fleming.
Suggest he had a role in the discovery of antibiotics and pose the question,
‘What prompted Fleming to investigate these chemicals in 1928?’
- Have the class develop research focus questions related to Fleming’s
work and plan a bibliographical search.
- Help the students, in groups, to use the library and Internet to obtain
relevant information.
- Have each group report back to the class on what they believe triggered
Fleming’s discovery of penicillin.
Extension
The information found could be used by groups to produce a two-minute
role play entitled, ‘The Moment of Discovery!’
Reflection
- If Fleming did not set out to discover penicillin, what made him
start the research?
- What might have been the consequences for our generation if he had
discarded the contaminated plate, as many had before?
- Reflect on how you last dealt with an experiment that did not do what
you expected it to do.
- If it were possible to cultivate a creative, insightful researcher
how would you suggest they be trained?