PHYSICAL CHANGES IN LATER LIFE, LIFE EXPECTANCY AND SENSORY ABILITIES.

Life Expectancy  Life expectancy increased from 49 years in to 67 in  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  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)

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