Life-span development, Santrock, Chapter 17, Physical development in late adulthood Test Bank.

life span - Answer the length of time an organism is expected to live life expectancy - Answer the number of years a person can expect to live Centenarians - Answer people who live past 100 years of age, the numbers of which are increasing by 7% each year factors that influence longevity - Answer - genetics, environmental factors including lifestyle, ethnic differences, gender, marital status, Telemores - Answer stretches of noncoding DNA at the ends of chromosomes evolutionary theory of aging - Answer natural selection has not eliminated many harmful conditions and nonadoptive characteristics in older adults cellular clock theory - Answer Leonard Hayflick's theory that the maximum number of times that human cells can divide is about 75 to 80. As we age, our cells have less capability to divide. free-radical theory - Answer A microbiological theory of aging stating that people age because when their cells metabolize energy, they generate waste that includes unstable oxygen molecules, known as free radicals, that damage DNA and other structures. mitochondrial theory - Answer aging is caused by the decay of mitochondria Sirtuins - Answer A family of proteins that have been proposed as having important influences on longevity, mitochondrial functioning in energy, calorie restriction benefits, stress resistance, and a lower incidence of cardiovascular functioning. mTOR pathway - Answer a cellular pathway involving the regulation of growth and metabolism that has been proposed as a key aspect of longevity hormonal stress theory - Answer The theory that aging in the body's hormonal system can lower resistance to stress and increase the likelihood of disease.