• 2022-05-30
    It can be inferred from the passage that all of the following are with of producing new strains of influenza viruses except ______ .
    A: two influenza viruses in the same animal recombining
    B: animal viruses recombining with human viruses
    C: two animal viruses recombining in one animal
    D: two animal viruses recombining in a human
  • D

    内容

    • 0

      Viruses can become a worldwide problem.

    • 1

      A differential medium is one in which A: Fungi and viruses grow differently. B: Two different bacteria can be distinguished. C: A particular nutrient is used differently by two different bacteria. D: Two different temperatures are utilized in the incubation period.

    • 2

      Which of the following statements is false? A: Viruses contain DNA or RN B: The nucleic acid of a virus is surrounded by a protein coat. C: Viruses multiply inside living cells using viral mRNA, tRNA, and ribosomes. D: Viruses cause the synthesis of specialized infectious elements.

    • 3

      In recent years viruses have been shown to cause cancer in chickens. Viruses have also been shown to cause cancer in mice, cats, and even in some primates. Viruses might cause cancer in humans.This is a reasonable hypothesis.

    • 4

      The most serious damage caused by the viruses is that ______. A: the computer's functions are lowered B: the normal programs are damaged C: all the information stored in the computer is gone D: the computer infected by the viruses can't be used any longer