Lecture One
Which of the following is written in the correct binomial nomenclature?
A. Salmonella Typhimurium
B. Salmonella typhimurium
C. Salmonella Typhimurium
D. Salmonella typhimurium
What does "Virulence" mean? Give an example of a highly virulent disease.
Virulence is a measure of the severity of an infectious disease.
Examples include Ebola and Marburg viruses
How does occupation affect someone's susceptibilty to disease?
Healthcare workers are exposed to all sorts of pathogens.
Agricultural workers are at risk for exposure to zoonotic diseases such as anthrax.
If a flagellum is rotating counterclockwise, is it propelling the cell forward or backward?
The cell will move forward!
What bacterium is responsible for the Black Death?
Yersinia pestis
How do viruses differ from other microorganisms?
- They are acellular, meaning they are not composed of cells.
- They can have a DNA or RNA genome (not both)
- They require the use of a host cell to multiply and survive.
What is the difference between a sign and a symptom?
A sign is something that the person checking the patient can see/measure.
A symptom is something the patient can feel.
What role do lysosomes have in destroying a phagocytosed pathogen?
Lysosomes fuse with a endosome/pagosome, then destroy (digest) the pathogen with its variety of hydrolytic enzymes.
Ultimately the digested contents of the lysosome are expelled from the cell
What enzyme is responsible for the supercoiling of DNA?
DNA Gyrase
REMEMBER THIS FOR UNIT THREE!
When looking at a cell under a microscope you observe the following:
- This cell has a nucleus, golgi complex, and ER.
- It has a cell wall made of chitin
What kind of organism is this?
This is a fungi. Is it eukaryotic or prokaryotic?
How did Edward Jenner contribute to Microbiology?
He used scrapings of cowpox blisters to innoculate someone to see if they would be protected against the closely related but far deadlier smallpox. (It did)
What are the 5 phases of infectious disease?
Incubation
Prodromal
Illness
Decline
Convalescence/Recovery
As you observe a bacterium, you note that it has a thin layer of peptidoglycan in its wall, as well as an outer membrane. Is this bacterium G- or G+?
This bacterium is Gram Negative!
Aquatic phototrophic microbes utilize these to help them stay buoyant and near the water's surface.
Gas vesicles!
DAILY DOUBLE: What is a phototroph?
What is a contractile vacuole?
An organelle found in free living eukaryotes that lack a wall. It prevents osmotic shock by removing excess water from the cytoplasm.
What do archaea and bacteria have in common? What differences are there between the cell types?
Similarities:
Both are prokaryotic unicellular organisms.
Differences:
Cell walls are different
Archaea are found in very extreme environments
This refers to an infection transmitted from a healthcare worker to a patient
Iatrogenic infection.
DAILY DOUBLE!
What is a nosocomial infection?
Why is the bacterial cell wall such an attractive target for antibiotics?
Because our cells lack a cell wall, therefore they will be unharmed by antibiotics.
Describe 3 things that ALL cell types have in common
- Cytoplasm
- DNA genome
- May be flagellated
- Have ribosomes!
What are three measures someone can take to prevent the spread of infection?
LOTS!
- Handwashing
- Use of proper PPE (goggles, apron, etc)
- Wipe down your bench after lab :)
Say you developed a strong passion for bread mold after taking this class... What field of microbiology would you end up studying?
Mycology!
Contracting a disease via a fomite would be an example of vertical or horizontal transmission?
Horizontal!
True or false: ALL bacteria have a cell wall
False! Can you name 2 that don't?
What is the difference between the rough and smooth ER?
Rough: Site of RNA translation by ribosomes
Smooth: Calcium storage, lipid/steroid synthesis, carbohydrate metabolism
Characterize the 3 components of the cytoskeleton:
Microfilaments: involved in intracellular traffic
Intermediate filaments: fibrous proteins that help maintain the cell shape
Microtubules: Pull apart chromosomes during mitosis, form parts of cilia/flagella