d. permanently greater spread in the ages at which people die
2. For most of human history, up to the modern era, life expectancy was probably about \_\_\_\_\_\_ years. a. 20–30 b. 30–40 c. 40–50 d. 50–60
a. 20–30
a. 40; 1
a. 20
5. Each of the following except \_\_\_\_\_\_\_ influenced the decline of mortality in the United States prior to World War II. a. improved diet b. better hygiene c. availability of penicillin d. availability of smallpox vaccinations
c. availability of penicillin
d. led to the spread of death control technology around the world.
b. Asia.
d. there are many routes to low mortality.
c. diets must adapt to circumstances.
c. our cells have a built-in time clock that eventually stops.
120
b. about 35 percent of the variability is due to inherited characteristics.
a. 0.
d. 15
15. The process of \_\_\_\_\_\_ describes the pattern that would exist if everyone survived to age 100 and then died shortly after that. a. rectangularization of mortality b. suppression of death rates c. gender inequality in mortality d. lifespan expansion
a. rectangularization of mortality
a. infectious diseases.
d. control over the environment.
c. noncommunicable conditions
a. tobacco use.
b. age-adjusted death rate
b. urban rather than rural residence