ECOLOGY
ENVIRONMENTAL ISSUES
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
modern preventive medicine
|
|
|
increase in life expectancy
|
|
|
improved waste disposal
|
|
|
increase in recycling and reusing products
|
Detailed explanation-1: -Births, Deaths, and Migration. Population growth rate depends on birth rates and death rates, as well as migration.
Detailed explanation-2: -In addition, the Industrial Revolution, which brought about an unprecedented demographic explosion. In the 19th century, the population doubled and in the 20th century, it even tripled, reaching 6 billion in the year 2000. Medical, scientific and economic advances led to this exponential growth.
Detailed explanation-3: -When demographers attempt to forecast changes in the size of a population, they typically focus on four main factors: fertility rates, mortality rates (life expectancy), the initial age profile of the population (whether it is relatively old or relatively young to begin with) and migration.
Detailed explanation-4: -Answer (b) Background extinction.