Answer to Question 1
a
Answer to Question 2
Social epidemiology is the study of causes and distribution of health, disease, and impairment throughout a population. Typically, the target of the investigation is disease agents, the environment, and the human host. Disease agents include biological agents such as insects, bacteria, and viruses that carry or cause disease; nutrient agents such as fats and carbohydrates; chemical agents such as gases and pollutants in the air; and physical agents such as temperature, humidity, and radiation. The environment includes the physical (geography and climate), biological (presence or absence of known disease agents), and social (socioeconomic status, occupation, and location of home) environments. The human host takes into account demographic factors (age, sex, and race/ethnicity), physical condition, habits and customs, and lifestyle.
Rates of illness and death are highest among the old and the young. Chronic diseases are illnesses that are long term or lifelong and that develop gradually or are present from birth; in contrast, acute diseases are illnesses that strike suddenly and cause dramatic incapacitation and sometimes death. Two of the most common sources of chronic disease and premature death are tobacco use, which increases mortality among both smokers and people who breathe the tobacco smoke of others, and alcohol abuse.
Prior to the twentieth century, women had lower life expectancies than men because of high mortality rates during pregnancy and childbirth. Preventive measures have greatly reduced this cause of female mortality, and women now live longer than men. Gender roles and gender socialization also contribute to the differences in life expectancy. Men are more likely to work in dangerous occupations. As a result of gender roles, males may be more likely than females to engage in risky behavior such as drinking alcohol, smoking cigarettes, using drugs, driving dangerously, and engaging in fights. Women are more likely to use the health care system with the result that health problems are identified and treated earlier, whereas many men are more reluctant to consult doctors.
Racialethnic differences are also visible in statistics pertaining to life expectancy. Numerous studies have found that people have a higher survival rate if they live in better-educated or wealthier neighborhoods than if the neighborhood is low income and has low levels of education. Among the reasons researchers believe that neighborhoods make a difference are the availability (or lack thereof) of safe areas to exercise, grocery stores with nutritious foods, and access to transportation, education, and good jobs. People of color are more likely to have incomes below the poverty line, and the poorest people typically receive less preventive care and less optimal management of chronic diseases than do other people.