Download Reading Guide for Week 2 – Bio260

Reading Guide for Week 2 – Bio260, Fall 2013
Colleen Sheridan
Stage 01 – Disease Transmission
In this unit we are trying to figure out how diseases like whooping cough, influenza, and HAIs are transmitted
and how their transmission through the environment can be reduced.
In this week’s reading you will learn about:
1. the ecology of bacteria and the human body
2. the protective role of the normal microbiota (most bugs are good!)
3. microbial control in the environment to reduce disease transmission
4. when transmission happens, some terms that help us to describe the characteristics of infectious
disease
5. Koch’s postulates: how to establish the cause of infectious disease
Chapter 16: Host-Microbe Interactions (16.1-16.2) (16.3-16.4 will be moved to Stage 02 – Colonization
and Infection!)
From this reading we find out that not all bacteria are bad. As a matter of fact most of the bacteria that grow on
our body help to protect us from disease-causing (pathogenic) microbes!
1. Be able to talk about Leeuwenhoek’s and Koch’s contribution to understanding the cause of infectious
disease.
2. What is a pathogen?
3. What does it mean to be immunocompromised?
4. Be able to describe the 3 types of symbiotic associations: mutualism, commensalism, parasitism.
5. What is the normal microbiota? Be able to name 3 common genera found on or in the body.
6. Be able to describe the protective role of the normal microbiota.
Chapter 5: Microbial Control (5.1-5.9)
So far in our story, we have found out that microbes are present everywhere in our environment and on our
bodies, that they can be transmitted from one host to the next through various mechanisms, and that they have
cellular structures that are made out protein, DNA, lipids, carbohydrates (or various combinations) that give
them certain cellular functions. Here we will learn about the various physical and chemical methods that can be
used to control microbial presence and growth so that we can reduce the transmission of disease. Particular
emphasis will be given to microbial control in the healthcare setting.
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6.
What is the difference between bactericidal and bacteriostatic?
What is the difference between sterilization and disinfection?
How are disinfectants different from antiseptics?
How did Joseph Lister and Ignatz Semmelweis contribute to the understanding of microbial control?
What parts of an organism are the most sensitive to some type of control?
In choosing some type of microbial control, what factors are important to consider? Are all organisms
equally sensitive?
7. List all of the methods that kill endospores.
8. Understand how each of the following physical methods control bacteria: Heat (dry heat, boiling,
autoclaving, pasterurization), filtration, freezing, dessication, radiation (ionizing radiation, non-ionizing
radiation, and microwaves).
9. Understand how the following types of chemicals control bacteria: Phenol/phenolics, halogens (iodine and
chlorine), alcohols, metal compounds (silver, mercury), soaps, quaternary ammonium compounds, and
biguanides.
10. OK, so what, if these methods denature proteins? What happens to a cell if its proteins are denatured? Be
able to explain what would happen to cellular function if the proteins in these cellular structures were
denatured:
1) fimbriae
2) cytoplasmic membrane
3) ribosomes
11. What technique would you use to control the growth of organisms in the following situations:
-plastic petri plates
-drinking water
-nutrient agar media
-surface of lab benches
-cleaning hands
-skin before injection
-sterilize a heat sensitive solution