Brad Darrach

Since 1850, the life span of the average American has increased from approximately forty-five to seventy-five years. In the following viewpoint, Brad Darrach argues that molecular biologists are making remarkable discoveries about the aging process that could increase human longevity by one hundred years or more. Darrach is a staff writer for Life, a monthly general interest magazine.

As you read, consider the following questions:

1. What feature of cancer cells do researchers hope to control, according to Darrach?
2. According to the author, why are nematodes ideal for studying aging?
3. How does human growth hormone affect the body, according to Darrach"

For more than a decade, with increasing success, molecular biologists all over the world have been struggling to answer a question as old as death: Why do we age and what—if anything&mdash...