Theories of Aging & Vocab

Question 1

Metabolic theory of aging

Answer 1

Organisms have only so much energy to expend in a lifetime - the rate of an organism’s metabolism is related to how long it lives

(research indicates that our circadian rhythms (the sleep–wake cycle) interact with caloric restriction in such a way that it matters when during the awake cycle feeding occurs, and the quantities and what exactly is eaten are major factors in whether the caloric restriction results in longer life, and the extreme reductions in calories needed to affect longevity usually lower quality of life)

Question 2

Cellular theory of aging

Question 3

Hayflick limit

Answer 3

in the cellular theory of aging - the upper limit number of possible divisions cells can make depending on the age of the organism

Question 4

Telomeres

Answer 4

the tips of chromosomes that shorten with every cell replication

Question 5

Telomerase

Answer 5

an enzyme needed in DNA replication to fully reproduce the telomeres when cells divide
(But telomerase normally is not present in somatic cells, so with each replication the telomeres become shorter)

Question 6

Oxidative stress

Answer 6

an imbalance between free radicals and antioxidants in the body

this can make free radicals damage DNA and proteins in the body
(can lead to cardiovascular disease and Alzheimers)

Question 7

Free radicals

Answer 7

highly reactive molecules produced randomly in normal metabolism that react easily with other molecules

Question 8

Antioxidants

Answer 8

molecules that stabilizefree radicals to become less reactive

Question 9

Cross-linking as a basis of biological theory of aging

Answer 9

certain proteins in human cells interact randomly and produce molecules that are linked in such a way as to make the body stiffer

Question 10

Mitochondria as a basis of biological theory of aging

Answer 10

changes that occur in mitochondria with aging have been associated with problems in movement and some cognitive functions, as well as with dementia, depression, and other mental disorders - these changes may trigger more general cellular dysfunction and eventually death

Question 11

Genetic programming theories

Answer 11

aging is programmed into our genetic code (family medical history, etc)