1. List and describe the four types of cancer.
2. What are the three classes of environmental agents that are shown to increase the risk of cancer?
3. Why does the flu vaccine developed each year not always work?
4. Name three organs of the lymphatic system.
5. The HIV virus is a retrovirus. Explain what is unique about retroviruses as a category.
6. List and explain the ABCDs of melanoma.
7. Explain what the difference is between the immune system and the immune response.
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