Developmental Psychology

Achieve Test Prep: Developmental Psychology

This is the oldest and most general aging theory. This theory postulates that the body wears out after being lived in and body parts deteriorate. The body is like a machine which wears out after too much use. 2. Cellular Accidents Every time a cell divides, there is a chance for mistakes to occur. Generally these mistakes are benign and do not cause problems. The only times these mistakes become a problem are when several mistakes occur together. Mutated cells have a decreased function as opposed to non-mutated cells. There are also free radicals, atoms with unpaired electrons, which may cause harm to the body. Free radicals are produced during metabolism and may damage DNA. Antioxidants such as Vitamin C and E soak up free radicals. 3. Error Catastrophe Error catastrophe occurs when the body can no longer contain the cell damage caused by cellular accidents. This aging theory helps to explain cancer and malignant tumors. 4. Immuno-senescence Aging and getting older are part of the life cycle. Researchers believe there is a programmed senescence for each cell. This notion is evidenced by the maximum lifespan. For humans, the maximum lifespan appears to be approximately one hundred and twenty years. Life span is not the same as life expectancy, which is approximately seventy to eighty years. Life span and life expectancy are different for each gender. 5. Genetic Clock The theory of a genetic clock is congruent with the idea of a programmed senescence. The genetic clock mostly likely resides in the ends of chromosomes, called telomeres . The evidence that genes help to regulate aging is shown well in individuals with Down syndrome. Individuals with Trisomy 21 (Down syndrome) typically do not live into late adulthood. These individuals typically die of heart disease or Alzheimer’s, which are diseases typical of late adulthood. Another genetic disease, progeria , shows the signs of aging. This disease results in accelerated aging with patients dying by age fifteen. Leonard Hayflick researched the effects of aging and the aging process. Through his research, Hayflick learned that cells stop multiplying after a certain number of divisions, regardless of cell condition. This number, the cap on divisions, is termed Hayflick Limit. The Hayflick Limit is different for each cell.

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