Chapter 1: A Case Study for Evolutionary Thinking: Understanding HIV

1.	HIV/AIDS can be transmitted by several routes. Which of the following correctly pairs a region with its most common mode of transmission? [Hint]
2.	The HIV virus is best characterized as [Hint]
3.	Match each feature of the HIV virus and its target cells to the correct function. [Hint] Using the pulldown boxes, match each item on the left to the corresponding item at right. A. transcribes viral RNA into viral DNA B. splices viral DNA into the host genome C. contains the genetic instructions for viral proteins D. HIV virions bind to this host cell receptor to begin their life cycles E. helps to prepare mature viral proteins by cleaving their precursors Choice A Choice B Choice C Choice D Choice E CD4 protein  [Hint] Choice A Choice B Choice C Choice D Choice E viral RNA  [Hint] Choice A Choice B Choice C Choice D Choice E reverse transcriptase  [Hint] Choice A Choice B Choice C Choice D Choice E protease  [Hint] Choice A Choice B Choice C Choice D Choice E integrase  [Hint]
4.	List the three basic stages of an HIV infection in an untreated patient. For each stage, state the pattern of HIV replication, the concentration of CD4 cells, and the action(s) of the immune system. [Hint] To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
5.	Which of the following contributes to the development of AZT resistance in HIV virions? [Hint]
6.	Which of the following best describes the evolutionary rationale behind Highly Active Anti-Retroviral Therapy (HAART)? [Hint]
7.	List and briefly describe the two levels of selection acting on HIV. For each, list one or two key characteristics of HIV that will be favored. [Hint] To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
8.	According to the transmission-rate hypothesis, a major cost of virulence in HIV is ___; a major benefit is ___. [Hint]
9.	This diagram represents the phylogeny (evolutionary history) of the HIV virus and its non-human primate relatives. Correctly match each label with its description. [Hint] For each item below, use the pull-down menu to select the letter that labels the correct part of the image. Choice A Choice B Choice C Choice D This node represents the common ancestor of a group of SIV viruses that have not been transmitted to humans.  [Hint] Choice A Choice B Choice C Choice D This node represents the common ancestor of all human HIV viruses and all of their non-human primate relatives.  [Hint] Choice A Choice B Choice C Choice D This node represents the common ancestor of all human HIV-1 lineages and their chimpanzee SIV relatives.  [Hint] Choice A Choice B Choice C Choice D This node represents the common ancestor of one group of human HIV-1 viruses and their closest chimpanzee SIV relatives.  [Hint]
10.	Evidence that transmission of HIV from an SIV relative in chimpanzees to humans has taken place multiple times includes the finding that [Hint]
11.	To be effective, an HIV vaccine would have to contain epitopes from the proteins found in many different strains of HIV. [Hint]
12.	Researchers are pessimistic about the prospects of developing an effective AIDS vaccine because ___ and ___. [Hint]
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