People in need of a heart or lung transplant are forced to wait until a potential donor organ is found. Researchers are hard at work, though, developing an alternative. This hour, we’ll talk about the possibility of growing replacement human organs inside cows, pigs and other animals – and we’ll talk about the ethics of the practice – the subject of a story in the November issue of Scientific American. We’ll be joined by Christine Gorman, the magazine’s senior editor for health, human biology and medicine.