Physical Changes in Later life Objective 11-2 Tyler Dean, Bailey Ford, Jannelle Webster

introduction Over time, our human life expectancy has increased greatly, however, our sensory abilities will still inevitably diminish over time.

Life expectancy: human’s greatest achievement 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.

Men Vs. Women 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.

Why don’t we wear out? 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 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.