For this information, see the Immune System at Work and Battling HIV activities. Make the Sample Western Blot Test transparency. Explain that all of the students in the room are well respected, wise doctors. As doctors, they will run the necessary tests. Here's What To Do Discuss the nature of inference with the students.
People use inference in a variety of everyday situations.
Have students brainstorm a list of such situations. You may want to put students in groups, giving each group a category to consider. Have students discuss and write down the results on the worksheet, as indicated. Discuss the results of the first test. HIV antibodies may have developed by then.