**Why do we age? Review the materials for this week and in your own words summarize 3 theories or hypotheses that explain why our bodies age.
**In the US and abroad, cosmetic surgery is tremendously popular. Many patients who request cosmetic surgery do so wishing to regain their once youthful appearance. Why do you think Americans are so concerned with the outward signs of aging, most of which are relatively harmless? Is this a positive or a negative social trend? Explain and support your response.