The Ageing Process

Question 1

What steps are involved in ageing on a cellular level?

Answer 1

Random molecular damage during cell replication
Damage made worse by inactivity, poor diet, chronic inflammation
This reduces the body’s reserve capacity (resilience)

Question 2

What is a telomere and what is the sequence in humans?

Answer 2

The DNA loop at end part of each chromosome arm

TTAGGG

Question 3

What is the Hayflick limit?

Answer 3

Proposed limit at which the telomere replicates and becomes too short (#x50)

Question 4

What can extend the shortened telomeres?

Answer 4

Telomerase

ribonucleoprotein complex

Question 5

In what cells is telomerase active?

Answer 5

Immune cells

Stem cells

Question 6

What can cause damage to macromolecules?

Answer 6

Ionising radiation (UV light)
Reactive oxygen species (diet, radiation, inflammation)
Extrinsic toxins (bisphenols)

Question 7

What are the 4 main cellular responses to damage?

Answer 7

Repair
Apoptosis
Senescence (deterioration)
Malignant transformation

Question 8

Describe the disposable soma hypothesis

Answer 8

Body’s main function is reproduction
After the reproductive age, there is little value in repairing body
Damage > repair

Question 9

Describe the anatgonistic pleiotropy hypothesis

Answer 9

Genes that were useful in early life become deleterious in late life

Question 10

What is fraility?

Answer 10

Loss of homeostasis and resilience

Question 11

How can fraility be measured?

Answer 11

Deficit accumulation (Rockwood)
Phenotypic (Fried Score)

Question 12

Describe the Rockwood model for fraility

Answer 12

Take 20-80 body systems (x)
Count number of deficits (y)
Y/X = score

Question 13

Describe the Fried score for fraility

Answer 13

1 point each:
unintentional weight loss
low grip strength
self-reported exhaustion
low physical activity levels
slow walking speed
3 or more = frail