The quest for the "Fountain of Youth" has long been a goal of both early explorers and modern scientists. It also driven a huge industry based on the premise that it's possible to slow down, stop, or even reverse the process of aging.

Choose one property of the human body (and mind), i.e. organ, organ system, tissue type and discuss how it changes with age and these changes affect total lifespan. Is there any current research in medical science that supports any way to slow its process of aging? What about the claims by the manufacturers of pharmaceuticals and/or nutritional supplements that some of their products have an effect on aging of the system you chose? Are any valid?