Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
22 Cards in this Set
- Front
- Back
|
1. what are the cellular theories?
|
programmed cell death
waste product theory cross linkage theory |
|
|
2. what are the physilogical theories
|
ehaxtion of irreplaceable supplies
decline in potass and lens gluthaine |
|
|
3. what are the organ-based theories?
|
immune theories
calorie restriction neuro-endocrine theories |
|
|
4. what are the genetic theories? programmed
|
heretibility of lifespan
modifer genes pleotrophic genes gene redundency |
|
|
5. what are the genetic theories? un-programmed
|
somatic mutation
DNA repair error catastrophe free radicals telomeres |
|
|
1. programmed cell death
|
cells have an intrinsic fixed (limited) capactity to divide therefore aging processes is controlled by 'celluar clock'
|
|
|
1. wast product theory
|
many human cell systems accumulate the age pigment lipofusion which i sbeleived to disrupt cell metabolism and cause agine
|
|
|
1. cross-linkage theory
|
irreversible covalent cross linking of DNA molecules leads to cellular dysfunction
|
|
|
2. exhaustion of irreplaceable supplies
|
with aging body, water composition declines. 30% loss of sodium and consequential loss of potassium is blamed for it
|
|
|
2. decline in potassium and lens gluthaine
|
supplies of gluthaione (anti-oxidant in the human lens) decreases linearly with age and cannot be replaced from elsewhere in the body
|
|
|
3. immune theories
|
atrophy of thymus glans with age decreases immune system efficiency leading to infections, autoimmune disease and cancer
|
|
|
3. calorie restriction
|
eat less live longer - calorie restricted diet increases a person's lifespan
|
|
|
3. neuro-endocrine theories
|
reduction in number of neuro-endocrine cells leads to aging
|
|
|
4. heretiability of lifespan
|
aging is a result of pre-wrtitten program that controls growth, development and aging
|
|
|
4. modifer genes
|
certain genes are suppressed until achievement of reproductive potential
|
|
|
4. pleiotrophic genes
|
genes beneficial in early life become harmful later in the lifespan
|
|
|
4. gene redundency
|
aging is casued by prevailing loss of non-repeated info from the genome
|
|
|
5. somatic mutation
|
radiation causes genetic mutations that lead to cellular dysfunction and death
|
|
|
5. DNA repair
|
ability to repair somatic mutations is directly correlated with lifespan potential
|
|
|
5. error catastrophe
|
random errors in synthesis of proten lead to accumulation of defective DNA
|
|
|
5. free radicles
|
molecules of ionized oxygen (have one extra electron) readily bond with protiens preventing them to carry on their functions
|
|
|
5. telemeres
|
repetitive DNA sequences at the end of chromosomes are progressivley shortened - wear and teae
|
