Download Reading Guide for Week 1

Reading Guide for Week 1 – Bio260
Colleen Sheridan
DUE Wednesday, April 9, 2014
Stage 01 – Disease Transmission
Did you know? 1) A paper published in March 2014 (just released!) found that 1 in 25 people hospitalized in
US medical care facilities in 2011 were infected in a medical care facility by a Hospital-associated infection
(HAI) while receiving care. 2) A pertussis (whooping cough) epidemic was declared in Washington State in
2011. 3) Measles can be contracted 2 hours after the infected individual has left a room! 4) The influenza
pandemic of 1918 killed ~50 million people worldwide, more than the death toll in the two world wars
combined.
How do you get an infectious disease? In this unit we are trying to figure out how infectious diseases (like
whooping cough, measles, influenza, and healthcare-associated infections (HAIs)) are transmitted and how their
transmission through the environment can be reduced by various microbial control methods.
Reading Assignment:
Chapter 1 (Microbial World), sections 1.3-1.5
Chapter 19 (Epidemiology), sections 19.1, 19.3, 19.5
Chapter 2 (The Molecules of Life), skim – you should already have a background knowledge of this
Chapter 3 (Microscopy and Staining), sections 3.1-3.9
In this week’s reading you will learn about:
1. Diversity and naming of microbes
2. Mechanisms of disease transmission and public health agencies who work to reduce it
3. Prokaryotic cellular structure, so we can understand how to control their presence in the
environment in order to reduce transmission of disease. Structure is also important in
understanding how to identify bacteria, how bacteria grow, how bacteria cause disease, and how
to treat their infection.
Chapter 1: Microbial World (Sections 1.3 – 1.5)
First off, what are microbes and how do we talk about them?
As you are reading, pay special attention to understanding about
the diversity of microbes in the world (living cellular microbes like bacteria, archaea, and some eukarya
such as algae, protozoa, fungi; and non-living microbes like viruses, viroids, and prions),
how bacteria are named through the Binomial System of Nomenclature (Genus species: Escherichia
coli, Staphylococcus aureus, Bordetella pertussis, etc…),
how tiny microbes are (eukaryotic cells: 10-100 µm; bacteria: 1-10 µm; viruses: 50-100 nm)
Chapter 19: Epidemiology (Sections 19.1, 19.3, 19.5)
Now you will work to understand how vaccine-preventable diseases (VPDs) like whooping cough (pertussis),
influenza, measles, and HAIs like Clostridium difficile, Staphylococcus aureus, and members of the family
Enterobacteriaceae are transmitted.
As you are reading, pay special attention to understanding about
how to describe the rate of disease in a population using the words endemic, epidemic, pandemic, and
outbreak
the reservoirs of infection, or the natural habitat of a microbe, and that people carrying the microbe can
have symptomatic infections or be asymptomatic carriers.
The portals of entry and exit into and out of the organism in order for the microbe to spread to a
new susceptible host through routes such as fecal-oral transmission, respiratory transmission,
sexual transmission, and vector transmission
the mechanisms of disease transmission like contact transmission (direct contact, indirect contact
through fomites, and droplet transmission), and transmission through food, water, air, and
vectors.
How public health organizations like the CDC, the WHO, the Washington State Department of Health,
and Seattle & King County Public Health work to control and prevent the spread of infectious
disease.
How HAIs are one of the top ten causes of death in the US, what different types of infections there are,
their common causes, the reservoirs of infection in healthcare (patients, environment, personnel),
the major mechanisms of disease transmission in healthcare settings (medical devices as fomites,
direct transmission from healthcare personnel, and airborne transmission), and hospital Infection
Control Committees and the CDC’s Healthcare Infection Control Practices Advisory Committee
(HICPAC) that work to control and prevent the transmission of infectious disease.
How Standard Precautions can help protect patients and personnel from infectious disease transmission
by recommending things such as hand-washing and care of the environment through cleaning
and disinfection.
We use antiseptics, disinfectants, and sterilization techniques (microbial control methods) in order to reduce the
likelihood of transmission of an infectious agent. Most of these chemicals and techniques work by destroying
critical cellular structures. To understand more about why these chemicals and techniques work you will read
about prokaryotic cell structure and function in Chapters 2 and 3. Here are some study questions to help you
get the most from these chapters:
Chapter 2: The Molecules of Life (Skim if you already know these)
You should already know these key biochemical concepts, but, if not, make sure you know the following:
1. covalent bonds, polar covalent bonds, hydrogen bonds
2. structure of water and why it is a polar molecule
3. why a molecule is hydrophilic or hydrophobic
4. pH
5. All about proteins!
Functions (where would you find them in a bacterial cell?)
Made of amino acids held together by covalent bonds called peptide bonds
Primary, secondary, tertiary, and quaternary structure (Figure 2.17) and the type of bonds that hold these
structures together (super important!!)
Protein denaturation (how it happens) (super important!!)
What happens to protein function if the protein is denatured? Why?
6. Carbohydrates
Functions (where would you find them in a bacterial cell?)
Monosaccharides are single units (simple sugar molecules), disaccharides are two units, polysaccharides
are many units.
7. Nucleic acids
Functions (RNA, DNA), (where would you find them in a bacterial cell?)
Nucleotides are single units
8. Lipids
Functions (where would you find them in a bacterial cell?)
Triglyceride = 3 fatty acids + 1 glycerol
Phospholipids = 2 fatty acids + 1 glycerol + 1 phosphate group
Why are phospholipids both hydrophilic and hydrophobic? Why is that important for cell membranes?
MORE ON BACK 
Chapter 3: Microscopy and Staining (Sections 3.1-3.9)
Pay special attention to what molecules make up these structures and what functions they do for the cell.
You’ll need to know this to understand how microbial control methods work (next week’s reading).
1. Know the difference between a bright-field light microscope picture and an electron microscope (scanning
or transmission) picture (Table 3.1)
2. What are the characteristic shapes (morphology) and groupings of bacterial cells?
3. Understand the differences between a prokaryotic cell and a eukaryotic cell.
4. Describe the following prokaryotic cell structures and their functions (In other words, what types of
molecules are they made of (protein, carbohydrate, nucleic acid, lipid) and how are they arranged?
What function does this structure do for the cell?)
• glycocalyx (differentiate between a capsule and a slime layer)
• flagella
• pili (fimbriae and sex pili)
• cell wall (be able to draw and label the complete molecular composition of Gram-positive and
Gram-negative cell walls in Figures 3.32a and 3.33a). Understand its role in regulating cell shape
during osmosis
• cytoplasmic membrane (be able to draw and label complete molecular composition from Figure
3.24 and briefly describe some of the essential functions this structure does: transport, energy
transformation, secretion, sensing environment)
• chromosome (in the nucleoid region) and plasmids
• periplasm
• cytoplasm
• ribosomes (Structure? Function? How do they differ from eukaryotic ribosomes?)
• storage granules
• endospores (What is the function of endospores? How are they made? What are the steps in the
synthesis of a spore? Do all bacterial cells make endospores? Name a bacterial genus that
produces endospores.)
Be able to provide an example of an organism that contains a structure above using the genus and
species name.