Concept explainers
(a)
To analyse:
The infectivity of enveloped viruses if they were prevented from budding.
Introduction:
Viruses comprise of a core of
(b)
To analyse:
If a lytic infection could be caused by injection of only the RNA of an influenza virus into a cell.
Introduction:
H5N2 virus infection caused a widespread and severe infection in millions of chicken and caused a great loss to poultry farms and food industry. The virus was named because of the presence of Hemagglutinin protein (H) that allows viruses to invade cells of the respiratory tract and the enzyme neuraminidase (N) that facilitates penetration of the virus in target cells by digesting mucus.
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Foundations in Microbiology
- a. Since viruses lack metabolic enzymes, how can they synthesize necessary components? b. Name some enzymes that viruses may have for invading and completing their cycles.arrow_forwarda. During which stages of an infectious disease does the host exhibit signs and symptoms? Is there a correlation between this and when a disease is communicable? b. Why are some viral diseases, like smallpox and polio, no longer seen in the United States? Why are many bacterial disease, like syphilis, no longer a death sentence? Think about how these two types of microbes infect humans. Why might we make an effort to treat viral diseases before infection but continue to treat bacterial diseases after infection? c. Based on the graph below, which pathogen is more virulent: Agent 1 or Agent 2? Explain. 100 Agent 1 LD5 = 400, Agent 2 LD50 = 600 25 100 200 300 400 500 600 700 800 900 1,000 Dose (organisms administered per animal) Percent mortality 75arrow_forwarda. Compare three characteristics of a bacterium and a virus.b. Why are viruses so hard to control?arrow_forward
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- a. What characteristics of viruses could be used to describe them aslife forms?b. What makes them more similar to lifeless molecules?arrow_forward1. Precise words:Find the nonspecific terms in the following sentences. Replace the nonspecific choices with more preciseterms or phrases (It is not necessary to change the sentence structure).(i) All OVE mutants showed enhanced iP concentrations.(ii) Plants were kept in the cold overnight.(iii) To provide proof of concept for our hypothesis, we studied a virus in its host cell.(iv) The present paper reports on continuing experiments that were performed to clarify thissurprising effect.(v) The first transition state is a little lower in energy than the second transition state. 2. Simple words:Improve the word choice in the following examples by replacing the underlined terms or phrases withsimpler word choices (do not change the sentence structure).(i) These data substantiate our hypothesis.(ii) The difference in our results compared to those of Reuter et al. (1995) can be accounted forby the fact that different conditions were used.(iii) For the purpose of discussing cell migration we…arrow_forwardWhich of the following processes occurs in both lytic and nonlytic viral infections?(i) Infected cell ruptures to release viral particles.(ii) Viral mRNAs are transcribed by the host-cell translation machinery.(iii) Viral proteins and nucleic acids are packaged to produce virions.arrow_forward
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning