Lecture 5

Question 1

Rate of living theories 1

Answer 1

Correlations between metabolic rate and lifespan in some animals -increase insects lifespan by stopping them from flying
- mammals increase lifespan (Cristofallo 1999) theory of limited energy

Question 2

Rate of living theories 2

Answer 2

Calorie restriction in rats and monkeys slows ageing and extends life by up to 60 percent

Okinawans eat 60 percent of the calories of a normal Japanese diet, 40 times the amount of centenarians

no evidence of those with strenuous jobs (eg athletes) age faster (hayflick 1994 95)

Question 3

Rate of living theories 3

Answer 3

How well bodies hormone regulatory system responds to stress decreases with age

Question 4

Cellular ageing theories

Answer 4

• Cells have a fixed number of divisions before dying number decreases with age (hayflick limit 96)
• why? DNA tips of chromosomes ‘telomeres’ need enzyme telomerase to fully replicate during cell division
• With a replication telomeres get shorter until too short to replicate (saretzki 2002)

Question 5

Cellular ageing theories

Dolly the sheep

Answer 5

Cloned from adult so life span shorter, started off with shorter telomeres

Question 6

Cellular ageing theories

Antioxidants

Answer 6

Antioxidants (vit a c e and coenzyme q) prevent o2 combining with molecules to form free radicals

• no ev increase lifespan
• ev suggests antioxidants delay onset of age related disease (cristofallo 96)

Question 7

Declines in sensory functioning

Answer 7

Impaired cognitive performance could be the result of sensory not cognitive declines or poor health

So screen for sensory decline and health and use sensory aids eg glasses

Question 8

Declines in the vision

Answer 8

75% of older need glasses (Bromley 1988) modest declines in sensitivity to mechanical stimuli means older people not as sensitive to detecting a foreign body in the eye

Less light enters the eye so require more lumination

Less lens elasticity difficult to adjust lens size and harder to accommodate to nearer objects

Question 9

Declines in vision 2

Answer 9

Cataracs common- scatter light and increase glare, careful when increase to limit glare

Diabetes damage receptor cells in the retina this is controlled with monitoring blood sugar

Vision function is in the brain to neurons in visual cortex with complex vision info is translated into meaningful signals

Question 10

Declines in audition

Answer 10

46% UK older people have a hearing impairment negatively associated with the quality of life makes social interaction more difficult

Ossicles of the middle yet stiffen, further losses affects all frequencies and leads to poor pitch discrimination

Hair cells dengerate poor transmission of high frequency sounds eg alarms

Question 11

Declines in audition 2

Answer 11

Degen of neurons in auditory nerve can distort signals salant 1996

hearing problems are the result of top-down cognitive and bottom-up sensory

Question 12

Declines in taste smell and touch

Answer 12

Taste- food tastes more bland no evidence that number of taste cells decrease so why loss of smell less socialising

Smell- ability to detect odours declines from the 60s abnormal changes are an indicator of later dementia (meisami 1994)
-Implications for safety, social interaction and acceptance of ageing e.g. reminisce

Touch- healthy sex life emerging as an important factor in healthy ageing