2. Look up apoptosis; find 3 or 4 papers that feature research on this topic. What are some potential applications of the concept of programmed cell death? What causes the cells to die?

3. Type in the term "cytokine" using an internet search engine and look for a cytokine Web page. What is a cytokine? From where do they come? Find information relating to the number of currently known substances, and describe two medical applications of cytokine therapy.

4. Type in the term cytokine on a search engine and look for a cytokine web page. Find out how many cytokines are currently known and describe several medical applications of cytokine therapy.