Transcript 11-2 (Part 1): Physical Changes in Later Life

PHYSICAL CHANGES IN LATER
LIFE, LIFE EXPECTANCY AND
SENSORY ABILITIES.
Life Expectancy
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Life expectancy increased from 49 years in 19509
to 67 in 2004.
Increased life expectancy is due to decreasing birth
rates.
Life expectancy differs for males and females;
males are more prone to dying.
Women outlive men by 4 years worldwide and by 5
to 6 years in Canada, the U.S., and Australia.
Physical Changes
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When the body ages, its cells stop reproducing and
the body becomes frail.
When you’re older, you’re more vulnerable to tiny
insults, such as hot weather or a fall.
Evolutionary Biologists proposed a theory that we get
worn out as we get older because once we’ve fulfilled
our gene-reproducing task, there are no natural
selection pressures against genes that cause
degeneration in later life.
Physical decline begins in early adulthood
Sensory Abilities
Visual sharpness, muscle strength, reaction
time, stamina, hearing, distance
perception, and the sense of smell
diminish.
 Adaptation to changes in light level slows
(the eye’s pupil shrinks and its lens
becomes less transparent)
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True or False
1. During old age, many of the brain’s
neurons die
2. The body is more vulnerable to a
mild flu bug at 80 than it is at 20.
3. A person’s ability to identify things
previously experienced declines with
age.
4. If they live to be 90 or older, most
elderly people become senile.
5. Older people experience reduced
amount of light reaching the retina.
Answers
1. False
2. True
3. False
4. False
5. True