Expert answer:bio – different questions with A+ result

  

Solved by a verified expert:The primary reason for the incredible success of viruses in their incredible diversity. The primarysources of this diversity are Blank 1 Blank 2 Blank 3 Blank 4Answer2 points Question 21.Briefly describe why viruses are said to exist as populations of sequences and not singlesequences. What is the technical term for this concept.AnswerPress Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac).Path: pWords:02 points Question 31.The primary reason Human infections by Ebola virus are largely localized to parts of Africa iswhich of the following (select one)?AnswerA.Africans have a gentic polymorphism that enhances their resistance to malaria, but makes them more susceptible to Ebola (and other filovirus) infections.B. Ebola is used as a bio­weopon by government militias fighting political instability incentral Africa.C. The primary animal reservoir for the Ebola virus is geographically restricted to AfricaD.The warm dry climate in Africa enables the virus to remain active outside the host forextended periods.2 points Question 41.The higher the mutation rate of an RNA virus, the more likely the virus will be able to succeed.Answer True False1 points Question 51.Although the polio virus has been around for centuries, it only became a significant healthproblem in the developing world in the 20th century due to (select one)?AnswerPolio was transmitted to humans by a zoonosis in the 1930’sVaccination programs for polio beganLoss of natural vaccination due to improved sanitation.Virus evolved to more pathogenic formHumans were better able to travel and migrate which enhanced dissemination of the virus2 points Question 61.The graph below shows the relationship between viral genome size and mutation rate. Explainthe observed relationship between genome size and mutation rate (3­5 sentences max).Note: The mutation rate is expressed as the number of substitutions per nucleotide pergeneration,. For viruses a generation is defined as a cell infection in viruses (?s/n/c).AnswerPress Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac).Path: pWords:02 points Question 71.Coronaviruses are a class of ssRNA viruses that are responsible for a number of respiratorydiseases including SARS and the recently identified Middle Eastern Respiratory Syndrome(MERS). Coronaviruses are the largest known RNA viruses with genomes ranging from 26­32kb. Coronaviruses are able to achieve such large genomes because they possess a gene not foundin other RNA viruses. Using what you have learned this semester, speculate in 3­4 sentences thelikely function of this gene that enables coronaviruses to possess such large genomes. Justifyyour answer.AnswerPress Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac).Path: pWords:02 points Question 81.RNA viruses tend to occupy broad ecological niches with multiple host species, while DNAviruses tend to coevolve with host with fewer host species.Answer True False1 points Question 91.List three factors that explain why there appears to be an increase in the number Emerging ViralDiseases globally. Justify each factor in 1­2 sentences.AnswerPress Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac).Path: pWords:02 points Question 101.Match the following Emerging viruses with the disease or symptoms they cause.Answer AnswerPolio VirusA.Read AnswerItems forQuestion 10 Transmission of virusto humans is highlydependent onWest Nileclimate/weatherVirusbecause it influencesRead Answerpopulations of rodentItems forQuestion 10vectorB. Emerged due to improved sanitation thatSinNombrebroke natural vaccination cycleRead Answer Virus was brought to Americas by earlierC.Items forQuestion 10 explorers. Beliveved to have wiped out native populations because they did notSeverehave immunity to virus.AcuteDRespiratoryFirst major viral epidemic documented to.Syndrome be spread by air travelVirus E. Brought to United States by insect vectorRead AnswerItems forQuestion 10 VariloaRead AnswerItems forQuestion 102 points Question 111.Explain why a virus that is well adapted to one species and causes no apparent disease can upona switch to a new host range cause severe disease (Max 3­5 sentences)?AnswerPress Tab to enter the content editor. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac).Path: pWords:02 points Question 121.What is the last name of the scientsist who accredited with the following quote:”In the battle by attrition, humans have a real problem competing with microorganisms. Here we are, here are thebugs, they’re looking for food, we’re their meal in one sense or another, how do we compete?”