Ageing Flashcards
define ageing
Progressive, generalised impairment of function resulting in a loss of adaptive response to disease
what is the Hayflick limit
with each cycle of cell replication, the telomere on the end of the chromosome shortens until eventually it is too short to replicate
what does a telomere consist of
multiple repeats of TTAGGG sequence
what can be used as a marker of biological age
telomere length
what substance can re extend the shortened telomeres, and in which cells is it active
telomerase, in cells that need to divide many times
what is the disposable soma hypothesis and what does it say about ageing
- body budgets the amount of energy and resources it uses - must find a balance between soma maintenance and reproduction
- ageing occurs due to an accumulation of damage over life time and multiple defensive/repair mechanisms contribute to ageing
what is antagonistic pleiotropy
a gene is beneficial to an organisms fitness early in life byt causes functional decline and ageing phenotypes later in life
who makes up the frailty group
older people who are at higher risk of adverse outcomes
what are the 2 ways to measure frailty
deficit accumulation and phenotype model
what is the deficit accumulation for frailty
what 5 things does the Fried score 1 point for
unintentional weight loss
low grip strength
self reported exhaustion
low physical activity levels
slow walking speed
what are the adverse things assoicated with multi morbidity
- High rates of adverse events, poorer QOL, greater healthcare use, institutionalization, disability and death
does being part of a social network increase survival trends in those over 75
yes
what effect does calorie restriction have on life span
may have positive effects on life span, to do with protection from oxidative stress (free radical theory of ageing)
does calorie restriction have a role in postponing malignancy onset
maybe yes
