The Ageing Process

Question 1

what is ageing

Answer 1

progressive, generalised impairment of function resulting in a loss of adaptive response to disease

Question 2

what causes human ageing

Answer 2

random molecular damage during cell replication

Question 3

what can increase ageing/cellular damage

Answer 3

inactivity
poor diet
inflammation

Question 4

7 factors contributing to ageing

Answer 4

Mutations in chromosomes 
Mutations in mitochondria 
Intracellular aggregates 
Extracellular aggregates 
Cellular loss (lack of stem cells/replacement) 
Cell senescence (useless/harmful cells) 
Extracellular protein crosslinks

Question 5

what is a telomere

Answer 5

end part of each chromosome arm

Question 6

what happens to telomeres in the ageing process

Answer 6

they shorten after every replication, eventually leaving to cell senescence as it is too short to sustain replication

Question 7

what is the hayflick limit

Answer 7

the limit to ageing - when the telomeres are so short they can no longer divide

most cells dont divide enough times to reach this limit

Question 8

what does telomerase do

Answer 8

a protein complex active in some cells which need to divide many times - re-extends the shortened telomeres

Question 9

what damage to macromolecules occurs during ageing

Answer 9

DNA mutations/breaks
Lipid per oxidation
Protein misfolding, aggregation, cross linking

Question 10

what causes damage to macromolecules in ageing

Answer 10

ionising radiation
reactive oxygen species (diet, radiation, inflammation).
Extrinsic toxins

Question 11

what 4 main cellular processes are causes by macromolecule damage

Answer 11

Repair
Apoptosis
Senescence
Malignant transformation

Question 12

what is the antagonistic pleiotrophy theory of ageing

Answer 12

that genes are beneficial in early life but detrimental in late life
act as a ‘time bomb’ in later life contributing to death of the organism from cell senescence

Question 13

what is frailty

Answer 13

loss of homeostasis and resilience causing increased vulnerability to external stresses

increased risk of falls, delirium, disability and death

Question 14

what are the 2 models of frailty

Answer 14

deficit accumulation

Phenotypic (fried score)

Question 15

how does the phenotypic model identify frailty

Answer 15

Unintentional weight loss 
Low grip strength 
Self-reported exhaustion 
Low physical activity levels 
Slow walking speed 

(3 or more = frail)

Question 16

how does the deficit accumulation model identify frailty

Answer 16

count how many body systems have a deficit - the index is deficits divided by the number of systems

between 0-1 is frail

Question 17

what difference does frailty make to health

Answer 17

minor illness can have a profound effect in frail people - high risk complications from hospitalisation

Question 18

true/false - multimorbidities and frailty is the same thing

Answer 18

false

you can have no multimorbidities and be frail or have multimorbidities and be robust

Question 19

what does physical activity protect against in old age

Answer 19

Heart disease 
Diabetes 
Cancers 
Mild depression 
Dementia and Alzheimers

Question 20

what are some medical characteristics of old age

Answer 20

multi-morbidity 
multiple medications 
Illness presenting in atypical ways 
falls, immobility, delirium 
need for rehabilitation