Exam 1 Flashcards
What percent of microbes are pathogenic
3%
Microbiology
Scientific study of microscopic organisms and viruses.
What is normal flora?
Microbes that live in or on your cells
Ratio of microbes to human cells?
10xs or 10:1
How many different species in our flora?
500-1000
Average weight of human flora?
3lbs
What do they mean by opportunists?
The microbe may take advantage which can lead to disease
When do you start acquiring flora?
During birth process, care givers, etc
What percent of o2 that we breathe is produced by microbes.
50%
How are microbes beneficial to plants
They are needed in the soil
How do cows, horses, sheep use microbes
To digest cellulose in their gut
How do ecosystems rely on microbes?
To enrich soil and degrade wastes
What products that we eat or use are produced by microbes?
Wine, beer, yogurt, cheese bread, nail polish remover, detergent, flavorings
Who invented the first microscope?
What was its magnification?
Robert Hooke
25x
Why were cells named cells?
What was the first thing Hooke viewed under the microscope?
Hooke saw open squares
Cork
Who first saw microbes
What did he read
What mag was his microscope?
Anton Von Leeuwenhoek
Hooked micrographia
200-300x mag
What are considered microbes? 6
Fungi(yeast, mold) Protists Protozoa Algae Bacteria/archae Viruses S
Define spontaneous generation
When was this believed?
Who was the first to challenge it?
Life arising from non living matter
A very long time before it was prove
Redi
What did redi’s experiment test?
What was his profession?
What did the experiment consist of?
What was the conclusion.
Spontaneous generation
Italian md
3 jars with meat in them, one open, one closed and one with gauze. There were inky maggots in the open jar.
Spontaneous generation false
What was pasteurs experiment?
How long did he incubate?
What was the conclusion?
He. Got some swan necked flasks.
Boiled some broth until it was sterile
Incubated flasks and checked everyday fore 18 months
No growth
Tilted flask, within hours microbes grew.
Spontaneous generation FALSE
How could Pasteur tell. If. Their. Was microbes. In. His broth?.
Cloudiness indicated microbe growth, clear meant now growth
How. Did. People control rate of. Infection from disease. In. The 1300s?
Quarantine
In the mid 1500s what was the new idea about how diseases were transmitted?
Italian md said via clothes, touch, utensils, etc
What was miasma?
Poisonous particles in the air transmitting diseas
Definite epidemiology
The study of where and when infectious diseases occur
Who was the guy who invented hand washing?
What were his observations?
He did he die?
A Hungarian doctor ignez sennel weis
29% vs 3% md side to midwife side women died of a fever
Suggested washing hands, it decreased death by 2/3
No one liked it, drove him crazy, he was fired left Vienna
Went insane and stabbed himself with contaminated scalpel, died with same fever
Who was the English md who studied a deadly diarrhea outbreak in London ?
What was his conclusion?
What was the disease?
John snow
Contaminated water source of infection
Cholera
What does vaccination do?
Prevents infectious disease
Who (nation) discovered a prevention to small pox?
How did they do it?
Did it work?
Chinese
Took scabs off dead my people blisters, ground them up and blew the dust into people’s noses
It worked!
What was the european approach to the Chinese vaccination?
Did it work?
Inserted scabs under the skin
It worked!
What fraction of kids died in the small pox outbreaks in the 1700s?
Before what age would they die?
1/3
3
What did Jenner observe and then test?
What did he write?
He many in England were vaccinated.
Observed that milk maids would get cow pox and then survive small pox
He injected the cow pus into a little boy and he lived.
Wrote pamphlets for doctors
Over 100,000 were vaccinated
What was needed to really see microbes?
More powerful microscopes
What did they see in the stool of cholera patients.
Bacteria
What experiment did Pasteur do that led him to believe that microbes are cause of infectious disease
The French hired him to find out what was making their wine taste bad, so he looked at it under the microscope saw bacteria. Told them to heat it up to kill everything and then add yeast.
Published his paper
What is the germ theory and who wrote it?
What three vaccines did he produce
MIcrobes are the cause of infectious disease
Pasteur
Chicken cholera, sheep anthrax, human rabies
Who thought of using phenol in the operating room? What caused him to try this? Whose paper did he read? How much did the death rate drop by? What is phenol? What did they later use instead?
Lister
Half of his patients were dying after surgery, wanted to up his odds
Pasteurs on spontaneous generations
the rate dropped by 2/3 when they dressed wounds with phenol
Phenol is caustic and highly toxic to human skin
Boric acid
Who wanted to verify the germ theory?
How did he do it?
Robert Koch
By using Koch,s postulates on sheep while studying anthrax.
What are kochs postulates? 4
- Find the same microbe in every case of the disease
- Isolate the microbe and grow it in pure culture.
- Inoculate a healthy host with pure culture and the identical disease must be produced
- Rue isolate the microbe from experimental host and compare microbe to pure culture, must be identical.
What is pure culture?
Only the one microbe is growing
What else did Koch invent?
Solid bacterial growth media, Petrie dish, stain microbes, aseptic technique.
Who set standards for hygiene in patient care and. Kept stats for all. Of it?
Florence. Nightingale
Who in vented the magic bullet and what is it?
Paul ehrlich
Kills microbes but not harm humans
How much magnification is the ocular piece?
10x
What are the two major types of microscopes?
Light and electron
What is the total mag of the light microscope?
What does immersion oil do?
What state can the bacteria be in?
100x
Increase resolution
Alive
What are the two kinds of electron microscope?
Scanning and transmission
What can you see with an SEM?
What is its max mag?
Surfaces of cells
650,000x
What can’t you see with a transmission microscope?
What is its max mag?
Internal surfaces
1,000,000x
Why do we stain?
I improve ability to see colorless microbes
What is the first step in staining?
Prepare a smear
What is a smear.
What amount of microbes?
Next step?
Thin film of microbes on a slide
PINPOINT
Air dry
What does “fixing” do?
How do we do it? (2)
Attaches microbes to the slide so they don’t rinse off, and it kills them
- use heat (we do this
- use chemicals (formalin)
What is this overall charge of most bacteria.
What charge is the stain/dye?
Negative
Positive
What is a simple stain?
What does it allow you to see?
Uses one + charged dye
Only one color
See size, shape, and arrangement of bacteria
What is a differential stain?
What do you see
What are the three examples?
Uses two + charged dyes Primary and secondary/counter stains 2 colors at the end See size, shape,arrangement, and something more Gram, acid fast, and endospore
Gram stain, what colors? After adding crystal violet what color are the bacteria? After iodine? After decolorizer? After safranin?
Purple and pink All bacteria are purple All bacteria are purple Gram + are purple, gram - are clear Gram + are purple, gram - are pink
What does adding iodine to the gram stain do?
Forms iodine crystal violet complexes that decrease solubility and get stuck under the gram positive cell walls
Why does the gram positive bacteria hold on the the crystal violet while the gram negative do not?
The crystal violet iodine complexes get stuck under the thick wall of gram positive cell walls where gram negative have thin cell walls so the deocolorizer washes it right out