C. Ray Greek and Jean Swingle Greek

C. Ray Greek and Jean Swingle Greek argue in the following viewpoint that animal experimentation is unscientific because it erroneously assumes that animals and humans are similar at the cellular and molecular level. In fact, the authors contend that human and animal physiology are so different that many of the drugs and treatments that are approved after animal testing turn out to harm and even kill thousands of people each year. Moreover, the authors contend that animal testing has not been responsible for major breakthroughs in medical science. C. Ray Greek is an anesthesiologist and Jean Swingle Greek is a veterinarian.

As you read, consider the following questions:

1. What difference between dogs and humans makes dogs unsuitable as test subjects for surgery on the aorta, according to the authors"
2. According to the authors, how...