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- Wed Jul 20, 2016 11:19 am
#27375
Passage Discussion
VIEWSTAMP Analysis:
Two general Viewpoints are introduced in this passage: that of the “prevailing view” of biology (line 5), and that of “some biologists” who have recently made a different suggestion (line 10).
The Structure of the passage is as follows:
This passage is a nicely structure (though scientifically worded) presentation of a new perspective on pathogens.
Arguments: The author of this passage presents information regarding the traditional perspective, and a new perspective, regarding pathogens.
The author’s Main Point here is to present this more recent understanding of why some parasites may incapacitate and overwhelm their hosts (depending on their virulence and mode of transmission), rather than reflect the benign relationship generally thought to exist between parasites and their hosts.
VIEWSTAMP Analysis:
Two general Viewpoints are introduced in this passage: that of the “prevailing view” of biology (line 5), and that of “some biologists” who have recently made a different suggestion (line 10).
The Structure of the passage is as follows:
This passage is a nicely structure (though scientifically worded) presentation of a new perspective on pathogens.
- Paragraph One:
To open this passage the author presents a main question: why do parasites sometimes overwhelm their host, contrary to the prevailing view of a benign relationship between host and parasite? In response the author presents the suggestion of some biologists, who say that even fatal pathogens can achieve evolutionary success if they can replicate and transmit more than they lose in the process.
Paragraph Two: In this paragraph the author discusses the relationship between a pathogen’s mode of transmission and its virulence. The rhinovirus (which causes the common cold) is presented as an example, whose transmission requires proximity, will not likely disable its victims, because doing so would not be evolutionarily beneficial to the parasite.
Paragraph Three: Here another pathogenic mode of transmission is introduced: that via vector, an organism that carries and transmits the infection (the mosquito is provided as an example of a vector). For such transmission, a disabled host can still provide the opportunity to spread, but the pathogen must be stronger to allow the mosquito a sufficient supply to transmit the disease.
Paragraph Four: In the final paragraph, the author presents medical literature’s general support of the premise that vector-borne pathogens tend to be more virulent, but there are exceptions. Some pathogens, such as diphtheria and tuberculosis, are called “sit-and-wait” pathogens, because they are directly transmitted and can survive outside their hosts, many for weeks or months, waiting for replacement hosts to come along. This long lifespan, as compared with the hours-long life of a rhinovirus, makes the sit-and-wait pathogens among the most dangerous.
Arguments: The author of this passage presents information regarding the traditional perspective, and a new perspective, regarding pathogens.
The author’s Main Point here is to present this more recent understanding of why some parasites may incapacitate and overwhelm their hosts (depending on their virulence and mode of transmission), rather than reflect the benign relationship generally thought to exist between parasites and their hosts.
Thanks!
Please review the above explanation and let us know if this helps! Thanks!