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30 Cards in this Set
- Front
- Back
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What are Prions? What do they cause? |
Prions are abnormally shaped infectious proteins that lack nucleic acid and cause mad cow disease. |
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How does chlorine work on a chemical level? |
Chlorine is a halogen that unfolds and denatures essential proteins, including enzymes. |
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Compare and contrast: Thermal Death Point Thermal Death Time Decimal Reduction Time |
Thermal death point is the lowest temperature that kills all cells in a broth in 10 mins. Thermal death time is the time it takes to completely sterilize a particular volume of liquid at a set temperature. Decimal reduction time is the time required to destroy 90% of the microbes in a sample. |
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Describe each biosafety level, and what precautions are in each level? |
BS1: handling microbes that don't cause disease in humans BS2: handling moderately hazardous agents BS3: all manipulation of microbes done in safety cabinets BS4: handling microbes that cause sever fatal disease; lab space is isolated and protective suits are required. |
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Bactericidal vs. Bacteriostatic |
Bactericidal use agents that destroy or permanently inactivate bacteria. Bacteriostatic use chemicals or physical agents to inhibit bacterial growth and metabolism; it doesn't result in complete destruction of the microbe. |
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What is selective toxicity, and why is it possible? |
Selective toxicity is the effectiveness of an antimicrobial agent to be more toxic towards a pathogen than to its host. This is possible due to the structural or metabolic differences between pathogen and host. |
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List and explain the ways antimicrobials act on pathogens. |
* Inhibit cell wall synthesis: selectively toxic to certain fungal or bacterial cells * Inhibit protein synthesis: target the differences between prokaryotic and eukaryotic ribosomes. * Disrupt cytoplasmic membrane * Inhibit general metabolic pathway * Inhibit necleic acid synthesis * Inhibition of attachment or entry into host cells |
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Narrow-Spectrum antibiotics vs. Broad-Spectrum |
Narrow-spectrum antibiotics are effective against very few pathogens. Broad-spectrum are effective against many pathogens. |
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List and describe the mechanisms of resistance. |
* Enzymes produce to destroy or deactivate drugs * Resistant microbes may slow or prevent entry of drug into cell * Target of drug is altered so that binding is less effective * Resistant cells may alter their metabolic chemistry * Resistant cells pump antimicrobial drug out of cell before it can act * Bacteria in biofilms can resist antimicrobials * TB produces MfpA protein, a decoy to protect that slows cellular division of TB |
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What are the portals of entry? |
Skin Mucous Membranes Placenta Parenteral Route: circumvents normal portals |
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Disease vs. Infection |
Infection is the invasion of a pathogen whereas disease results only if the pathogen multiplies enough to adversely affect the body. |
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What is the role of adhesion in pathogenicity? |
The process by which microbes attach to hosts in order to establish colonies. **"If it doesn't attach it won't attack"** |
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Difference between symptoms, signs, and syndromes. |
Symptoms are subjective characteristics of a disease that can be felt by the patient. Signs are objective manifestations that can be observed or measured. Syndromes are a group of symptoms and signs that together characterize a particular disease. |
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Endotoxin vs. Exotoxin |
Endotoxins or lipid A are potentially fatal toxins released from the lipopolysccharide layer of the cell wall of dead and dying gram negative bacteria. Exotoxins are toxins secreted by a pathogenic microorganism into its environment. |
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Define: endemic, sporadic, epidemic, and pandemic |
Endemic: a disease that occurs at a relatively stable frequency within a given area or population Sporadic: a disease that occurs in only a few scattered cases within a given area or population during a given period of time Epidemic: a disease that occurs at a greater than normal frequency for a given area or population Pandemic: the occurrence of an epidemic on more than one continent simultaneously |
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Compare and contrast the 3 nosocomial infections. |
Exogenous: Pathogen acquired from the health care environment. Endogenous: Pathogen arises from normal microbiota as a result of factors within the health care setting. Iatrogenic: Results from modern medical procedures. Also, Superinfections: Use of antimicrobial drugs inhibits some resident microbiota, allowing other microbes to thrive |
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Stages of Infectious Disease |
•Incubation period •Prodromal period •Illness •Decline •Convalescence |
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What are three characteristics that makes Listeria Monocytogenes so pathogenic? What three diseases does it cause?
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Three characteristics that make it so pathogenic are it is gram-positive, it is non-endospore forming, and it is found in soil, water, mammals, birds fish, and insects.
The three diseases: sepsis, meningitis,spontaneous abortion. Along with pneumonia. |
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What is the difference between latent and active TB? What makes it so contagious?
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Latent TB, a person has a TB infection, but the bacteria remains in their body in an inactive state, causes no symptoms and is not contagious. Active TB, a person becomes sick and can spread it to others. It is very contagious because it is spread from person to person through microscopic droplets released into the air: coughs, speaks, sneezes, spits, laughs or sings.
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What is Vibrio Cholera? How is vibrio cholera transmitted? How does vibrio cholera cause disease?
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* It's a Gram Negative Bacteria that causes gastrointestinal disease * It can be transmitted by ingesting food or water contaminated with feces. *Once the bacteria enters our system, it will have to trespass one of our first mechanisms of defense, the stomach acids, the very few that do survive will grow a flagellum and make its way to the small intestine and the mucosa of the epithelial cells, where they will release the toxins that will cause loss of sodium in our bodies by diarrhea.
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How does H. pylori overcome the acidity of the stomach? How does it get into the lining of the stomach?
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* H.pylori possesses the enzyme urease which neutralizes stomach acid. * H.pylori, burrows through the stomach's protective mucus layer to reach the underlying epithelial cells. It then attaches to the cells' cytoplasmic membranes and multiplies. Then the mucus layer is thinned by a triggering of inflammation by bacterial toxins and destruction of mucus producing cells. Thinning allows acidic gastric juice to digest the stomach lining, perforating the epithelial layer. |
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What diseases does Bordetella Pertussisis cause and what are the symptoms. Describe how the toxins affect the lungs?
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Bordetella pertussis is the bacteria that causes whooping cough. Symptoms of whooping cough are a mild to severe cough, starting with a mild, cold like cough and processing to a bad cough. A fever, runny nose, and apnea (in babies) are symptoms of whooping cough. When pertussis is in its second stage it causes horrible coughing fits that can last for minutes at a time. |
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What makes Clostridium Difficile so pathogenic? What are some statistics for C .diff?
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*C. diff produces spores which are very hardy and resistant to high temperatures. Spores are passed in the stools of people who have C. diff in their gut. Spores can persist in the environment (for example, on clothes, bedding, surfaces, etc) for several months or years. The spores can also be spread through the air (for example, when shaking bedclothes when making a bed).
*Nearly 20% of hospital patients obtain thisbacteria during their stay, normally elderly |
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Explain the pathogenicity of the Human Papilloma Virus. What are some pros and cons of the HPV vaccine?
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HPV enters the body via the basal epithelium layer, where it encodes its proteins. These proteins then interfere with cell functions that usually prevent abnormal cell growth. Vaccine pros: high immunogenicity. Cons: potential adverse side effects, and the recommended 3-shot series over the period of 6 months can be difficult to follow.
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Explain why the Herpes virus is so pathogenic. What are some of the world wide statistics concerning the infection and transmission of this pathogen?
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Herpes is pathogenic because you can pass it to someone unknowingly due to not having any signs and symptoms. The virus can enter the body through a portal of entry, shed or spread to another person, lye dormant (latency period), and then reactivate.
67% of the population has HSV |
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Explain how the plasmodium causes malaria disease in the body (in 5 steps)
cont. on next card... |
1. When an infected Anopheles mosquitobites a human it releases sporozoites into the human's bloodstream. 2.The sporozoites enter the livercells where they develop into merozoites. 3. The merozoites are released from theliver cells, enter the blood stream and infect red blood cells and reproduce until the red blood cell burst. 4. Merozoites continue to infect more red blood cells repeating the cycle of replication and bursting until many infected red blood cells are present in the blood stream causing affects of Malaria.
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5th step
(cont.) Explain how the plasmodium causes malaria disease in the body (in 5 steps) |
5. Sexual products are produced by some merozoites called gametocytes that can be ingested by a mosquito who bites the human. This will allow Malaria to be spread to the next human the mosquito feeds on, continuing the process of vector transmission for Malaria.
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What are three important facts about Tapeworms?
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Tapeworm infestations are usually asymptomatic. Tapeworms develop in beef and pork in part of their lives.
Tapeworms absorb food through their cuticles. |
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How is N. Fowleri transmitted? How does it affect our nervous system?
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It is transmitted when a N. fowleri trophozoite enters a host’s nasal mucosa when infected water goes up the host’s nose. N. fowleri destroys the host's central nervous system.When the protozoa enters the brain, it sees the brain as nourishment and food.The brain-eating amoeba secretes enzymes and toxins which kills brain cells. |
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How does Ebola cause bleeding and hemorrhaging?
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When a person contracts Ebola, the virus gets in the body’s cells and replicates very quickly. In a normal, healthy human body clotting factors circulate the blood stream and a reable to stop bleeding when necessary. The Ebola virus causes Ebola virus glycoprotein’s to attach to the cells. This increases the permeability of the cells. The clotting proteins start forming small blood clots all over, clogging blood vessels causes spontaneous hemorrhaging and bleeding as blood leaks out of the vessels. This can cause shock and ultimately lead to death.
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