BIOLOGICAL CLASSIFICATION
VIRUSES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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genetic engineering mistkaes
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humans coming in contact with isolated habitats
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mutation of existing viruses
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the overuse of antibiotics
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Detailed explanation-1: -21.6 Summary. Newly emerging viruses: Increased contact with animals, primarily due to the expansion of the human habitat, is the cause for the emergence of new viruses. Newly emerging viruses include HIV, Ebola virus, SARS-CoV, and MERS-CoV.
Detailed explanation-2: -Changes in the environment such as rainforest developments have led to an increase in contact between wild animals and humans. As a result, viruses which only existed in rainforests are able to be transmitted to a new human host. Climate changes such as global warming are another cause for the emergence of new viruses.
Detailed explanation-3: -As a virus replicates, its genes undergo random “copying errors” (i.e. genetic mutations). Over time, these genetic copying errors can, among other changes to the virus, lead to alterations in the virus’ surface proteins or antigens. Our immune system uses these antigens to recognize and fight the virus.
Detailed explanation-4: -Virus-induced gene mutations are probably due to insertions of fragments of viral DNA (or cDNA) into the host chromosomes; at least some of these mutations are capable of transpositions and reversions.