5-2 Limits to Growth                                                          Name _________________________________________

1.  Once the sea otters became protected their numbers increased for a while.  Now, the numbers are decreasing. 
       Why?  __________________________________________________
2.  A ______________________________________ factor causes population growth to decrease.
3.  What does a panda eat?  _________________________________________
4.  What are four density –dependent limiting factors? 
        _____________________________________________________________________________________
5.  When two species compete for resources, over time they may evolve to occupy separate __________________
6.  ___________________________ - ____________________ relationship is one of the best known mechanisms of population control.
7.  Examine Fig 5-7.  In general, when the moose population increases, what happens to the wolf population? ______
       In 1980, the wolf population reached its highest level.  What happened right after this point? _______________
8.  What parasite attacks the sphinx moth larva?   (Fig 5-8) _____________________________
9.  What human activities can limit populations (density-independent factors)
            ________________________________________________________________________________________
10.  What can kill suguara cactuses in Arizona? ________________________________________________

Issues in Biology

11.  When did the Endangered  Species Act become a law? _______________
12.  Why might some people want to take the wolves off the Endangered Species List?
           _________________________________________________________________________________________
13.  Do you personally think the wolves should remain protected?
          __________________________________________________________________________________________

5-3 Human Population Growth

14.  List two factors which caused human population to grow quickly:  (the book lists a few)
          __________________________________________________________________________________________
15.  According to Malthus, what factors would limit human population growth?
         ___________________________________________________________________________________________
16.  The scientific study of human populations is called ____________________________________________
17.   More developed countries, like the United States have [ fewer / more ] children than less developed countries.
18.  Which two countries lead the world in population growth? ____________________________________________
19.  _________________ - _________________    ________________________ show the population of a country broken down by gender and age group.
20.  See Fig 5-13.  Which country is growing the fastest? ______________________________
                                What percent of the population of U.S. is  25-29 years old?  ____________________
                                                                                                                               (hint, you need to add the males and females)
21.  Name a  life threatening disease may affect growth rates in some countries?  _____________________________
22.  The world population growth may slow by 2050 if countries move toward demographic _____________________