You will use information on the World Wide Web to answer a series of questions.

EXERCISE 1:
STRATEGIES IN THE WAR AGAINST AIDS

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Although preventive behavior is the best defense against the Human Immunodeficiency Virus, treating people with existing infections is vital to winning the war against AIDS. Researchers use their knowledge of transcription, translation, the life cycle of retroviruses, evolution, receptors, and vaccines to devise new solutions to this complex and serious problem. Your understanding of these concepts will help you to follow the latest trends in AIDS research.

Print out the worksheet below and use the links to answer the following questions.

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Name _____________________________________________________

 

Link and Think: Strategies in the War Against AIDS

1. Although there are several approaches to the treatment of AIDS, all treatments fall under four general strategies in the table below. Treating HIV describes four treatments, links 2 through 5 on the story map. Can you categorize the treatments described in these two articles? Each article gives a number to the treatments it describes--write this number in the appropriate column.
   

   	Strategies Against AIDS
   	Prevent attachment	Prevent reverse transcription	Prevent integration of viral DNA	Prevent production of new virus
   Treating HIV (2-5)

   
   
2. AZT was one of the first drugs available for the treatment of AIDS. Which of the following treatment strategies does it fall under? Circle your answer.
   1. Prevent attachment
   2. Prevent reverse transcription of viral RNA to DNA
   3. Prevent integration of viral DNA into host genome
   4. Prevent production of new virus
   
   

Prevent Attachment

3. As you read on page 785 of your textbook, HIV attacks the T4 cells of the immune system. In order to enter the cell, HIV must first "dock" on two receptors on the T4 cell. What are these receptors called? Read "Treating HIV" to find out what the receptor and co-receptor are called, then circle them below.
   

   CD4

   CD5

   CXCR4

   CCR5

   CDC

   
   
4. A very small percentage of the American population lacks one of these receptors due to a deletion in the receptor gene. This group of people may never develop AIDS, even years after being exposed to HIV. Which receptor do they lack?
   

   CD4

   CD5

   CXCR4

   CCR5

   CDC

   
   
5. Treating HIV discusses a "prevent attachment" strategy. Write the name of the receptor in the chart.

   Resource	Strategy targets which receptor?
   Treating HIV

   
   

Prevent Reverse Transcription

6. How is HIV's RNA genome translated into DNA?
   1. HIV directs RNA polymerase to work in reverse
   2. HIV brings reverse transcriptase into the cell, which makes new DNA from the viral RNA template
   3. HIV harnesses the cell's own reverse transcriptase
   
   

Prevent Integration of Viral DNA

7. How could the number of T4 cells with HIV genes increase within an individual even if no new T4 cells are infected?
   
   

Prevent Functional Protein Production

8. Which three strategies target viral enzymes?
   1. Prevent attachment
   2. Prevent reverse transcription of viral RNA to DNA
   3. Prevent integration of viral DNA into host genome
   4. Prevent production of new virus
   
   
9. What does protease do?
   1. It clips proteins into pieces
   2. It translates protein into RNA
   3. It dissolves the viral coat, allowing the virus to escape into the cell
   4. It clips DNA
   
   

Check your work here.

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Unit 8 Index

Learning Links
Chapter 29 || Chapter 30 || Chapter 31 || Chapter 32 || Chapter 33 || Chapter 34

In the News || Link and Think
Spotlight on Careers || Teachers' Lounge

In the Community
Chapter 29 || Chapter 30 || Chapter 31 || Chapter 32 || Chapter 33 || Chapter 34