Question

population growth
how is population growth naturally regulated?
why? the current world population is estimated to be over 7 billion. at present the number of births usually exceeds the number of deaths, which means that the population is increasing, and is estimated to reach 9 billion by 2040. in 1750 the world population was estimated at less than 800 million. how are growing populations such as ours controlled and supported, and can they continue to grow indefinitely?
model 1 - population growth
refer to model 1.
a. what is the term used for populations moving into an area?
b. what is the term used for populations leaving an area?
c. name two factors that cause an increase in the population size.
d. name two factors that cause a decrease in population size.

Explanation:

• For part a, immigration is the term for populations moving into an area.
• For part b, emigration is the term for populations leaving an area.
• For part c, birth and immigration increase population size.
• For part d, death and emigration decrease population size.

Answer:

a. Immigration
b. Emigration
c. Birth, Immigration
d. Death, Emigration