Exam 26: Introduction to Viruses

In 2009, a flu pandemic was believed to have originated when viral transmission occurred from pig to human, thereby earning the designation "swine flu." Although pigs are thought to have been the host for the 2009 virus, sequences from bird, pig, and human viruses were all found within this newly identified virus. What is the most likely explanation for the presence of sequences from bird, pig, and human viruses?

Which of the following events or characteristics is the most likely explanation for why an individual experiences regular herpesvirus-mediated cold sore or genital sore flare-ups?

A bacterium is infected with an experimentally constructed bacteriophage composed of the T2 phage protein coat and T4 phage DNA. The new phages produced would have ________.

If a viral host cell has a mutation that interferes with the addition of carbohydrates to proteins during processing in the Golgi apparatus, which of the following processes is most likely to occur?

What is difference between an epidemic and a pandemic?

Which of the following methods would be best to use for distinguishing between an infectious agent that is a virus and one that is a prion?

Which of the following types of viral genomes could be copied using reverse transcriptase?

Which of the following characteristics is typical of the lytic cycle of a bacteriophage?

Use the following figure and information to answer the question below. Cells were infected with approximately 1,000 copies of either virus A or virus B at the 0 time point. At five-minute intervals, a sample of the virus and cell mixture was removed. All intact cells were removed from the sample, and the number of viruses per milliliter of culture was determined. Based on the data provided, the lytic cycle of virus A is closest to ________.

A researcher is studying a single plant infected with tobacco mosaic virus (TMV). She crushes three of the plant's leaves in a small amount of water and stores the sample in the refrigerator overnight. The next day she sprays the mixture onto a new set of tobacco plants she had recently trimmed and repotted. Which of the following results will most likely occur?

Which of the following best defines prions?

Which of the following correctly explain the effect that treating a viral infection with antibiotics has on the course of the infection?

If a viral host cell has a mutation that interferes with the addition of carbohydrates to proteins during processing in the Golgi apparatus, which of the following processes is most likely to occur?

Which of the following correctly describes the viral assembly process?

Which of the following processes can be effective in preventing the onset of viral infection in humans?

Which of the following statements accurately describes the lysogenic cycle of lambda (λ) phage?

Use the following figure and information to answer the question. Cells were infected with approximately 1,000 copies of either virus A or virus B at the 0 time point. At five-minute intervals, a sample of the virus and cell mixture was removed. All intact cells were removed from the sample, and the number of viruses per milliliter of culture was determined. Based on the data provided, the lytic cycle of virus B is closest to ________.

Humans have harmless E. coli strains that reside in the intestines. O157:H7 is an E. coli strain reported to cause several food poisoning deaths. Evidence suggests that the virulence of O157:H7 is caused by genes from a virus that infects bacteria. Considering this evidence, which of the following statements most likely explains how the O157:H7 population acquired the genetic variation that distinguishes it from the harmless E. coli strains?

Emerging viruses arise by ________.

RNA viruses require their own supply of certain enzymes because ________.