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47 Cards in this Set
- Front
- Back
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Viruses are
1. 2. 3. 4. |
1. submicroscopic
2. obligate intracellular 3. parasites 4. Distinctive from living organisms 5. Energy parasites |
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What kind of genome do viruses have?
What is this genome packaged in? |
Viruses have a nucleic acid genome.
The nucleic acid genome is packaged in a protein coat capsid. |
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What two organisms confound the definition of "obligate intracellular parasite"
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Rickettsiae and Chlamydiae can exist outside the cells of their hosts for only a short period of time. They are prokaryotic organisms with specialized intracellular parasitic lifecycles.
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How are virus particles produced?
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Virus particles are produced from the assembly of pre-formed components.
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T/F:
Virus particles grow outside the host. |
FALSE:
Virus particles themselves (virions) DO NOT GROW or undergo division |
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T/F:
Viruses cab make their own energy? |
FALSE:
Viruses lack the genetic information necessary for the generation of energy or for protein synthesis (ribosomes) |
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Two Views,
Are viruses alive inside the cell? |
YES and NO.
Inside the host cell, viruses are alive Outside the host they are complex assemblages of inert chemicals |
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What is the first record of virus infection?
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The first record of virus infection was poliovirus in ancient Egypt (in 3700 BC)
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What did Ramses V die from?
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Ramses V died from smallpox in 1196 BC. Pustular lesions were found on body.
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What virus was notable in ancient China?
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Smallpox virus was endemic in China by 1000 BC
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What did the Chinese invent in regard to virus strategy?
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The Chinese invented "variolation"
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What did Edward Jenner come up with?
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Edward Jenner came up with the Smallpox vaccine
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Who constructed the first microscopes used to look for bacteria?
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Antony van Leeuwenhoek constructed the first microscopes and used it to look at bacteria.
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Who is responsible for the 'germ theory'?
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Robert Koch and Louis Pasteur jointly proposed the 'germ theory' of disease
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Which two groups of gram(-) bacteria are obligate intracellular parasites?
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chlamydia and rickettsia
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How are Chlamydia and Rickettsia different from virus?
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Virus has either DNA or RNA. Bacteria have both DNA and RNA.
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T/F:
Rickettsiae and Chlamydia can exist outiside the cells of their hosts. |
TRUE.
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T/F:
Can a virus multiply outside the body in things like food or water? |
NO
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T/F:
Viruses can make their own ATP |
FALSE:
Viruses lack the genetic information necessary for the generation of energy or for protein synthesis. They are absolutely dependant on their host cell for energy. |
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What is a Virion?
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A viorion is the virus stage when it is NOT in contact with a host cell. It is by itself alone acting like nothing more than a static organic particle which has NO internal biological activities occuring in it. This is the non living state. They can stay dormant like this waiting for the right host to come along.
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What is the Virus?
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The stage when the virion is no longer dormant b/c the right host has come along. At this point, it becomes happy and 'activated'. This means it now acts like a living organism by doing things like reacting to its environment and directing its efforts toward self-replication. Any stage of infection
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What is probably one of the oldest known viruses?
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Polio
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Invented smallpox vaccination
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Edward Jenner
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Constructed first microscopes and saw bacteria
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Antony van Leeuwenhoek
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Proposed 'germ theory'`
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Robert Koch and Louis Pasteur
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What are Koch's Postulates?
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1. The agent must be in every case
2. It must be isolated and grown in vitro 3. The disease must be reproduced when a pure culture of the agent is innoculated into a healthy susceptible host 4. The disease must be isolated from the same host it now infects. |
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What is Dmitri Iwanowski credited for?
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He showed that extacts from diseases tobacco plants infected with TMV virus could transmit the virus to healthy plants after passage through ceramic filters which could trap it.
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What is Martinus Beijerinic credited with?
In whose steps did he follow? |
He was the first to develop the modern idea of the virus which he referred to as contagium vivum fluidum ' soluble living germ'.
He followed in the footsteps of Dmitri Owanowski |
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Coined the term contagium vivum fluidum 'soluble living germ'
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Martinus Beijerinick
Confirmed and extended Iwanoski's work on TMV and was first to develop modern idea of the virus. He was the first to develop the modern idea of a virus which he referred to as a "soluble living germ" |
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Showed that virus was responsible for foot and mouth disease. Similar in experimnet to Beijerinick's work with tobacco plant and TMV.
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Freidrich Loeffler and Paul Frosch
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Freidrich Loeffler and Paul Frosch did what?
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Showed that virus was responsible for foot and mouth disease. Similar in experimnet to Beijerinick's work with tobacco plant and TMV.
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Was Loeffler and Frosch's work appreciated by the public?
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No. Despite showing that viruses infected plants and animals, people were reluctant to believe humans could also be affected.
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Karl Landsteimer and Erwin Popper are responsible for what?
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They showed that poliomyelitis was caused by a 'filtrateable agent'- the first human disease to be recognized as being caused by a virus.
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Were Landsteimer and Popper's work appreciated by the general public? In opposition to what scientists?
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They showed that poliomyelitis was caused by a 'filtrateable agent'- the first human disease to be recognized as being caused by a virus. The public was finally convinced in oppopsition to Loeffler and Frosch's work with foot and mouth disease.
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Landsteiner and Popper worked with what disease? What was said to be the cause of this disease?
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Popper and Landsteiner worked with poliomyelitis. They showed it was caused by a 'filtrateable agent' the first human disease to be recognized as being caused by a virus.
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The first human disease to be recognized as being caused by a virus, a 'filtrateable agent'. Who is responsible for the discovery?
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Poliomyelitis.
Popper and Landsteinner |
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What does 'bacteriophages' mean? Who was the first to recognize them?
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'Eaters of bacteria'
Frederick Twort and Felix d'Herelle were the first to recognoze bacteriophages "eaters of bacteria" |
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Frederick Twort and Felix d'Herelle are credited with what?
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They were the first to recognize bacteriophages.
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Name scientists who used bacteriophage viruses as models for their work
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Salvador Luria
Max Delbruck |
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The history of virology involved ...
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The development of experimental tools
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Credited with the attentuation of rabies
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Louis Pasteur
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What virus did Louis Pasteur work with
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Louis Pasteur is accredited with the attenuation of rabies
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Credited with discovering Tobacco mosaic virus which led to whole plants being used to study plant viruses
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Iwanowski.
Russian botanist who showed that extracts from diseased tobacco planys could transmit disease to other plants after passage through ceramic filers fine enough to trap bacteria |
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What significant discovery is Walter Reed credited with?
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Walter Reed demonstrated that yellow fever was caused by a virus and spread by mosquitos
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Worked with the disease yellow fever
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Walter Reed. Demonstrated that yellow fever was caused by a virus and spread by mosquitos
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What are some problems with Koch's Postulates applied to Virology?
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Many viruses do not cause illness in all infected individuals, a requirement of postulate #1. An example is poliovirus, which causes paralytic disease in about 1% of those infected. Further compromising postulate #1 is the fact that infection with the same virus may lead to markedly different diseases, while different viruses may cause the same disease. Postulates #2 and #3 cannot be fulfilled for viruses that do not replicate in cell culture, or for which a suitable animal model has not been identified.
Also problems with human experimentation |
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What are Koch's postulates regarded as?
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Koch's postulated are generally regarded as proof that an infectious agent is responsible for a specific disease
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