Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
Bacteria are ubiquitous. What does this mean?
|
they are found everywhere
|
|
We contact numerous microorganisms daily. How do we come into contact with them?
|
every time we breathe in, eat, drink, pick up on skin, every time we touch something
|
|
Some bacteria live on the surface of our body and...
|
slough off with dead skin
|
|
What happens to most bacteria that are swallowed? |
they die in stomach acid or are eliminated in feces
|
|
What are pathogens?
|
something that noticeably damages the body
|
|
How many bacteria are pathogens that cause damage?
|
relatively few
|
|
Microorganisms can have symbiotic relationships. What are the 3 types? |
--mutualistic (or mutualism) --commensalism (or commensalistic) --parasitic |
|
What is mutualistic?
|
both partners benefit (like gut organisms) |
|
What is commensalism?
|
one benefits and the other is neither harmed or benefited (like skin bacteria)
|
|
What is parasitic?
|
one benefits and the other is harmed (anything bad like giardia)
|
|
How does the normal microbiota protect the host-- What is the protective role of normal microbiota? |
--cover the site where pathogens would bind to prevent attachment --consume nutrients that would otherwise support the growth of undesirable organisms --produces compounds toxic to other bacteria |
|
How does the normal microbiota protect the host-- What do antibiotics do? |
inhibit intestinal microbiota
|
|
How does the normal microbiota protect the host-- C-Diff: |
--endospore former --remove antibiotics |
|
Hygiene hypothesis-- What is the hygiene hypothesis? |
limited exposure to microbes causes more allergies
|
|
Hygiene hypothesis-- The immune system learns to reduce the response to microbes that routinely inhabit the gut as well as food. This prevents... |
the immune system from overreacting to harmless microbes
|
|
The dynamic nature of normal microbiota-- A healthy human fetus is _____ until just before birth |
sterile
|
|
The dynamic nature of normal microbiota-- How do changes occur? |
in response to hormonal changes and food we eat
|
|
Koch's Postulates-- What are Koch's postulates? |
criteria Robert Koch used to establish that Bacillus anthracis causes anthrax
|
|
Koch's Postulates-- What are the 4 criteria? |
1) the microorganism must be present in every case of the disease 2) the organism must be grown in pure culture from diseased hosts 3) the same disease must be produced when pure culture of the organism is introduced into susceptible hosts 4) the organism must be recovered from the experimentally infected hosts |
|
Koch's Postulates-- Limitations of Koch's postulates: Treponema pallidum causes syphilis, so |
grow in rabbit testicles, not petri dish
|
|
Koch's Postulates-- Limitations of Koch's postulates: Cholera, polio... |
don't always show signs or symptoms |
|
Koch's Postulates-- Limitations of Koch's postulates: Periodontal disease... |
is microbial (multiple organisms working together to cause disease)
|
|
Koch's Postulates-- Limitations of Koch's postulates: HIV... |
--no known animal hosts --ethical and moral issues using humans |
|
Damaging effects-- Damage may help pathogen to... |
exit and spread
|
|
Damaging effects-- Vibio cholera induces... |
watery diarrhea, up to 20 liters/day, which can contaminate water supplies
|
|
Damaging effects-- Bordetella pertussis triggers.. |
severe coughing, pathogens released into the air
|