A chemical called dioxin is produced as a by-product of some chemical manufacturing processes. Trace amounts of this substance were present in Agent Orange, a defoliant sprayed on vegetation during the Vietnam War. There has been continuing controversy over dioxin effects on soldiers exposed to it during the war. Some animal test have suggested that dioxin can be lethal and can cause birth defects, cancer, liver and thymus damage, and immune system suppression, while others have revealed inconclusive results. For example, a hamster is not affected by a dose that can kill a guinea pig. Even more confusing are the effects of dioxin on humans.
Researchers have shown that dioxin enters a cell and binds to a protein that in turn attaches to the cell's DNA. How might this mechanism help to explain the variety of effects dioxin has on different systems in animals? How might you explain how a particular individual became ill as a result of exposure to dioxin?