Schule, Abteilung: HBLVA17 Chemie, Abteilung Biologie
Jahrgang: 3. Jahrgang
Lehrer/in: Mag. Dr. Andrea Pichler-Wallace
Schuljahr: 2012/2013
Gegenstand: Biologie und Mikrobiologie
Thema: Sterile Working and Bacterial Control
Activity type/s
Classroom
format
Time
1. Watching a video and circling specific words
2. Answering questions
3. Answering a question from a video
4. Reading a text and drawing a timeline
5. Writing questions to find missing information in the text
6. Matching terms and definitions
7. Dicsussing an experiment and gaining critical thinking skills
8. Consolidating content by explaining a graph
1-4, 6. Individual work
5, 7. Pair work
8. Whole class
90 minutes
Procedure
1. Students watch a video to spark the interest. While watching a second time they
should circle the correct words in the transcript.
2. Students answer questions by choosing from a set of different aswers provided. Then
they write down the answers next to the questions
3. Students answer a question referring to the video.
4. Students read a text and draw a timeline. The teacher draws a timeline which is not
correct on the board. The students have to compare their timeline with the teacher’s
timeline to find the mistake.
5. Students write down questions to fill the gaps in a text. The only way of
communication between the group members is writing.
6. Students match topic-related terms with the appropriate definitions.
7. The students design an experiment. They have to discuss their ideas with their
partner. This should make them think about experiments for the laboratory part of the
class.
8. Students discuss a graph.
Resources
Handout: Sterile Working and Bacterial Control
Content-related
learning outcome
Students know the difference between disinfection and sterilization.
Students understand different aspects to control microbial growth.
Students are able to design an experiment for their practical work.
Students can read and listen for detail.
Students can extract information from a text and create a timeline.
Students can form sentences to describe the content and link the sentences in a logical
way.
Students can form questions to obtain missing information.
http://www.youtube.com/watch?v=4lmwbBzClAc (17.11.2012)
http://en.wikipedia.org/wiki/Bacteria (17.11.2012, adapted)
Bauman, Robert W. (2005). Microbiology. Brief Edition. San Francisco: Benjamin
Cummings. pp. 262-268
Language-related
learning outcome
Source/s
Mag. Dr. Andrea Pichler-Wallace
BMb – Biolgie und Mikrobiologie – 3. Jahrgang
Student’s version
Sterile working and bacterial control
Activity 1a. Watch the video (http://www.youtube.com/watch?v=4lmwbBzClAc). This spot done by
Nicole Brady of KOB-TV in Albuquerque, New Mexico, shows how many germs can accumalate on
your cellular phone.
Activity 1b. While watching the video a second time, circle the correct words in your transcript.
Mag. Dr. Andrea Pichler-Wallace
BMb – Biolgie und Mikrobiologie – 3. Jahrgang
Activity 2. Choose the correct answers (a-h) from the options given below to answer the questions 1-5.
Write the answers into the grid. There are two answers which you do not need to use.
Questions
Answers (see below)
1. How many general types of microbial control
are there?
2. What are the general types of microbial
control called?
3. Does sterilization eliminate all microbes?
4. Are there other techniques that are
considered to be some kind of disinfection?
5. How is disinfection different from
sterilization?
Answers. There are two extras that you don’t need.
a. Yes, it is.
b. Yes, there are.
c. It is the destruction of most microorganisms and viruses on nonliving tissue.
d. There are sterilization and disinfection.
e. There are two.
g. Yes, it does.
h. No, it does not.
Activity 3. Answer the following question: Did the reporter from the video sterilize or disinfect her
phone?
Answer: ____________________________
Activity 4. Read the description of the historic events below and draw a time line.
In 1676, Antonie van Leeuwenhoek was the first person to observe bacteria by using a
microscope. He was the first microbiologist but called his observations "animalcules". The
name “bacterium” was introduced in 1828. In 1859, Louis Pasteur showed that
microorganisms cause the fermentation process. His contemporary Robert Koch was a
pioneer in medical microbiology. He worked on cholera and tuberculosis and was the first
scientist who developed a series of tests that are still used today to prove the germ theory of
disease. In 1884, Hans Christian Gram developed a staining method to differentiate bacterial
species (Gram-positive and Gram-negative). In 1910, Paul Ehrlich developed the first
antibiotic that selectively killed spirochaetes which are the cause of syphilis. Sir Alexander
Fleming discovered the antibiotic substance penicillin from the mold Penicillium notatum in
1928. A major step forward in the study of bacteria was the recognition in 1977 by Carl
Woese that archaea have a separate line of evolutionary descent from bacteria. In 1995
Craig Venter, Hamilton Smith, Claire Fraser and colleagues finished the first complete
genome sequence of a microorganism: Haemophilus influenza.
Source: http://en.wikipedia.org/wiki/Bacteria (adapted)
Mag. Dr. Andrea Pichler-Wallace
BMb – Biolgie und Mikrobiologie – 3. Jahrgang
Activity 5. Getting the missing information...
Get in pairs. One of you reads text A, the other one reads text B. You need to find the missing
information to fill in the gaps in your text. Imagine, you and your friend are in jail, but on different sides
of the wall with a very small hole in it. Since your friend has the information you need to complete your
text, write down questions you need to ask him/her on a piece of paper and send it through the small
hole. Your partner does the same. Then you and your partner answer the questions and send the piece
of paper through the hole again. Both of you have a look at the anwers now an try to fill in the gaps in
your text.
A.
Physical methods of ___________ __________ include exposure of the microbes to extremes of heat
and cold, desiccation, filtration, osmotic pressure, and radiation. It is important for microbiologists to
use correct terminology for describing microbial control. In its strictest sense, _____________ refers
to the removal or destruction of all microbes, including viruses and bacterial endospores, in or on an
object. (It does not apply to prions).
The term aseptic describes an environment or procedure that is free of ____________ by pathogens.
For example, vegetables and fruit juices are available in aseptic packaging. Surgeons and laboratory
technicians use aseptic technique to avoid contaminating a surgical area or laboratory equipment.
Disinfection refers to the use physical or chemical agents known as __________ to inhibit or destroy
microorganisms, especially pathogens. Unlike sterilization, disinfection does not guarantee that all
pathogens are eliminated. The term is only used for treatment on inanimate (lifeless) objects. When
a chemical is used to treat skin or other tissue, it is called antisepsis and the chemical is called an
______________.
Degerming is the removal of microbes from a surface by scrubbing, such as washing your hands or
preparing an area of the skin for injection.
_______________ is the process of disinfecting places that are used by the public (to meet accepted
public health standards). Thus the only difference between disinfecting dishes at home in a dishwasher and sanitizing them in a restaurant is the location - private versus public.
Pasteurization is the use of heat to kill pathogens and reduce the number of microorganisms in food
and beverages. Milk, fruit juices, wine, and beer are commonly pasteurized.
B.
Physical methods of microbial control include exposure of the ____________ to extremes of heat
and cold, desiccation, filtration, osmotic pressure, and radiation. It is important for microbiologists to
use correct terminology for describing microbial control. In its strictest sense, sterilization refers to
the __________ or ______________ of all microbes, including viruses and bacterial endospores, in or
on an object. (It does not apply to prions).
The term ______ describes an environment or procedure that is free of contamination by pathogens.
For example, vegetables and fruit juices are available in aseptic packaging. Surgeons and laboratory
technicians use aseptic technique to avoid contaminating a surgical area or laboratory equipment.
__________ refers to the use physical or chemical agents known as disinfectants to inhibit or destroy
microorganisms, especially pathogens. Unlike sterilization, disinfection does not guarantee that all
pathogens are eliminated. The term is only used for treatment on inanimate (lifeless) objects. When
a chemical is used to treat skin or other tissue, it is called antisepsis and the chemical is called an
antiseptic.
___________ is the removal of microbes from a surface by scrubbing, such as washing your hands or
preparing an area of the skin for injection.
Sanitization is the process of disinfecting places that are used by the public (to meet accepted public
health standards). Thus the only difference between disinfecting dishes at home in a dish-washer and
sanitizing them in a restaurant is the location - private versus public.
Pasteurization is the use of heat to kill _____________ and reduce the number of microorganisms in
food and beverages. Milk, fruit juices, wine, and beer are commonly pasteurized.
Mag. Dr. Andrea Pichler-Wallace
BMb – Biolgie und Mikrobiologie – 3. Jahrgang
Activity 6. Match the correct terms from the list provided with the appropriate definitions.
-cide/-cidal, disinfection, sterilization, antisepsis, aseptic, -stasis/-static, degerming, pasteurization,
sanitization
Activity 7. Read the text and design an experiment. Discuss with your partner.
A student inoculates Escherichia coli into two test tubes containing the same sterile liquid medium,
except the first tube also contains a drop of a chemical with an antimicrobial effect. After 24 hours of
incubation, the first tube remains clear while the second tube becomes cloudy with bacteria. Design an
experiment to determine if this amount of the antimicrobial agent is bacteriostatic or bactericidal against
E. coli.
Activity 8. Look at the chart and discuss in class why different microorganisms have different succeptibilities
to antimicrobial agents.
Mag. Dr. Andrea Pichler-Wallace
BMb – Biolgie und Mikrobiologie – 3. Jahrgang
Teacher’s version
Sterile working and bacterial control
Activity 1a. Watch the video (http://www.youtube.com/watch?v=4lmwbBzClAc). This spot done by
Nicole Brady of KOB-TV in Albuquerque, New Mexico, shows how many germs can accumalate on
your cellular phone.
Activity 1b. While watching the video a second time, circle the correct words in your transcript.
Check if the students understand all the words and discuss any other options suggested by your students.
Mag. Dr. Andrea Pichler-Wallace
BMb – Biolgie und Mikrobiologie – 3. Jahrgang
Exercise 2. Choose the correct answers (a-h) from the options given below to answer the questions 1-5.
Write the answers into the grid. There are two answers which you do not need to use.
Questions
Answers (see below)
1. How many general types of microbial control
are there?
There are two.
2. What are the general types of microbial
control called?
There are sterilization and disinfection.
3. Does sterilization eliminate all microbes?
Yes, it does.
4. Are there other techniques that are
considered to be some kind of disinfection?
Yes, there are.
5. How is disinfection different from
sterilization?
It is the destruction of most microorganisms and
viruses on nonliving tissue.
Answers. There are two extras that you don’t need.
a. Yes, it is.
h. No, it does not.
Activity 3. Answer the following question: Did the reporter from the video sterilize or disinfect her
phone?
Answer: disinfect ____________________________
Activity 4. Read the description of the historic events below and draw a time line.
In 1676, Antonie van Leeuwenhoek was the first person to observe bacteria by using a
microscope. He was the first microbiologist but called his observations "animalcules". The
name “bacterium” was introduced in 1828. In 1859, Louis Pasteur showed that
microorganisms cause the fermentation process. His contemporary Robert Koch was a
pioneer in medical microbiology. He worked on cholera and tuberculosis and was the first
scientist who developed a series of tests that are still used today to prove the germ theory of
disease. In 1884, Hans Christian Gram developed a staining method to differentiate bacterial
species (Gram-positive and Gram-negative). In 1910, Paul Ehrlich developed the first
antibiotic that selectively killed spirochaetes which are the cause of syphilis. Sir Alexander
Fleming discovered the antibiotic substance penicillin from the mold Penicillium notatum in
1928. A major step forward in the study of bacteria was the recognition in 1977 by Carl
Woese that archaea have a separate line of evolutionary descent from bacteria. In 1995
Craig Venter, Hamilton Smith, Claire Fraser and colleagues finished the first complete
genome sequence of a microorganism: Haemophilus influenza.
Source: http://en.wikipedia.org/wiki/Bacteria (adapted)
Mag. Dr. Andrea Pichler-Wallace
BMb – Biolgie und Mikrobiologie – 3. Jahrgang
Activity 5. Getting the missing information...
Get in pairs. One of you reads text A, the other one reads text B. You need to find the missing
information to fill in the gaps in your text. Imagine, you and your friend are in jail, but on
different sides of the wall with a very small hole in it. Since your friend has the information
you need to complete your text, write down questions you need to ask him/her on a piece of
paper and send it through the small hole. Your partner does the same. Then you and your
partner answer the questions and send the piece of paper through the hole again. Both of you
have a look at the anwers now an try to fill in the gaps in your text.
Activity 6. Match the correct terms from the list provided with the appropriate definitions.
Activity 7. Read the text and design an experiment. Discuss with your neighbor.
A student inoculates Escherichia coli into two test tubes containing the same sterile liquid medium,
except the first tube also contains a drop of a chemical with an antimicrobial effect. After 24 hours of
incubation, the first tube remains clear while the second tube becomes cloudy with bacteria. Design an
experiment to determine if this amount of the antimicrobial agent is bacteriostatic or bactericidal against
E. coli.
Mag. Dr. Andrea Pichler-Wallace
BMb – Biolgie und Mikrobiologie – 3. Jahrgang
Prepare several test tubes containing the same sterile liquid medium. Inocculate different concentrations of
the first tube (that contained the chemical) and let those cultures incubate.
If the antimicrobial agent was bactericidal against E. coli none of the cultures would grow. If the
antimicrobial agent was bacteriostatic at some dilution the bacteria would start to grow again.
Activity 8. Look at the chart and discuss in class why the different microorganisms have different
succeptibilities to antimicrobial agents.
Endospores are the most resistant forms of life. For example, endospores can survive more than 20 years in
70% alcohol and scientists have recovered viable endospores from Egyptian mummies (thousands of years
ago).
The cell wall of some mycobacteria contain large amounts of waxy lipids which protect them from most
water-based chemicals.
Cysts – also cell wall.