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

Objective 11-2
Tyler Dean, Bailey Ford, Jannelle Webster
Over time, our human life expectancy has
increased greatly, however, our sensory
abilities will still inevitably diminish over
time.
Worldwide, life expectancy has increased from 49
years in the mid-twentieth century to 67 in the
early twenty-first century.
 Life expectancy exceeds 80 in some developed
countries like the United States and Canada.

 Women
outlive men and outnumber men
at most ages past early infancy.
 Men are more prone to dying.
 By age 100, the females outnumber males
5 to 1; however, few of us live to 100.
 After the age of 30, the risk of death
doubles every eight years.
 The body ages and its cells stop
reproducing, leaving our bodies more
vulnerable to illness and infection.
 Evolutionary
biologists believe that the
answer relates to our survival as a species.
 There are no natural selection pressures
against genes that cause degeneration later in
life.
 Sensory
abilities’ decline begins in early
adulthood, but we are not usually acutely
aware of it until later in life.



Visual sharpness diminished, and adaption to
changes in light level
Muscle strength, reaction time, and stamina
diminish
Also hearing, distance perception and sense of
smell diminishes.