Question

1. In the study of population growth, a J-shaped curve represents                 

a. a steady rate of population growth                   b. exponential growth          

c. an increasing rate of population growth that becomes very rapid

d. a population that grows rapidly at first and then maintains a steady population level

e. a population that is declining                 f. (b) and (c)

2. A. Is it reasonable to expect that exponential growth in any species can continue forever?

_____Yes                  _____No                    ____It cannot be determined

B. Explain your answer to part A of this question using one sentence.

3. If modern humans have been in existence for about 250,000 years, about how many years did it take for the human population to reach one billion humans?             a. 1000 years

b. 10,000 years        c. 50,000 years                     d. 249,850 years

4. About how long did it take the human population to grow from one billion to two billion?

a. 100 years              b. 1,000 years                       c. 10,000 years                     d. 50,000 years

5. About how many years does is take today to add another one billion humans to the population?

a. 1 year        b. 12-15 years          c. 30 years                d. 50 years                e. 100 years

6. The population of the earth today is about                  a. 1-2 billion              b. 3-4 billion

c. 7-8 billion               d. 10-12 billion

7. Explain what is meant by the carrying capacity of an ecosystem.

8. When a forest is burned killing all of the plants and animals, and if new plants and animals enter the cleared land, which of the following is/are true? Select all correct.

a. over many decades, a greater diversity of species will occupy the formerly cleared land

b. over many decades, a more complex food web will develop, compared to the food web in the first few years after clearing the land

c. after many decades, nutrients will be recycled by the ecosystem more effectively than they were recycled immediately after the land was cleared

d. removal of one or two species in the first year after clearing will have a greater effect on the ecosystem than removing one or two species in the 80^th year after clearing

9. Which of the following is associated with the clearing and burning of the tropical rain forests?

(Select all correct answers)

a. more soil erosion             b. more carbon dioxide released into the atmosphere  

c. loss of species diversity              d. increased instability of the earth’s ecosystems

10. Which of the following are the primary causes of the increase in carbon dioxide in the atmosphere?           (select all correct answers)        a. burning of fossil fuels      b. clearing of forest land

c. too much harvesting of fish from the ocean                d. the accumulation of CFC’s in the air

11. The increase of CO₂ is believed to contribute to what environmental problem? (Select all correct)

a. acid rain                b. global warming                 c. reduction of the ozone layer      d. alkaline rain

12. Which of the following is/are likely to be serious effects of the increasing of CO₂ in the atmosphere? (Select all correct)            a. increase in skin cancer                   b. flooding of coastal areas

c. climate change leading to unpredictability in crop production          d. increase in powerful storms

13.A. What has caused a “hole” in the ozone layer in the upper atmosphere?

13.B.  Which of the following is/are effects of the reduction in ozone in the upper atmosphere?

(circle all correct answers)              a. flooding of coastal areas            b. increased skin cancer                 

c. climate change leading to unpredictability in crop production          

d. destruction of phytoplankton that carry out photosynthesis in aquatic ecosystems

14. Which country would you expect to have a higher rate of population growth: U.S. or Mexico?

15. When an industrial nation reaches a certain level of affluence (wealth) its population tends to

a. grow more rapidly            b. decline rapidly                  c. remain fairly constant or grow very slowly

d. show what is called an S-shaped curve                      e. (d) and (c)

16. The change in the rate of population growth described in # 15 is called the

a. democratic transmission            b. demagogic transmission            c. demographic transition

d. automatic transmission               e. manual transmission

17. If the human population and our levels of use of natural resources are is now so high as to threaten the stability of the ecosystems that we need for survival, three broad strategies are possible to deal with these problems.   One strategy is to pass laws that force families to have only two children.  Which of the following are likely results of such a strategy? (Select all correct answers)

a. the world population would stop growing immediately                      

b. the world population would stop growing in 20-30 years

c. social unrest could occur from such a dictatorial policy

18.  If the human population and our levels of use of natural resources are is now so high as to threaten the stability of the ecosystems that we need for survival, three broad strategies are possible to deal with these problems.   One strategy is to do nothing and see what happens.  Which of the following are likely results of such a strategy? (Select all correct answers)

a. the world population might go so far over the carrying capacity that the population would fall rapidly, with the loss of hundreds of millions of human lives from malnourishment and disease

b. the world population would reach the carrying capacity and reach a stable plateau level

c. the world population will continue to increase rapidly but scientists will find a way to support more than 15 billion humans by use of better technology

19. If the human population and our levels of use of natural resources are is now so high as to threaten the stability of the ecosystems that we need for survival, three broad strategies are possible to deal with these problems.   One strategy is to raise the standard of living of the world’s poorest families and to curb consumption of the wealthiest people.  Which of the following are likely results of such a strategy? (Select all correct answers)

a. the world population will stop growing in about two generations

b. the continued increase in the human population will require switching to renewable sources of energy and recycling of most of the products we use

c. significant changes in our economic systems would be required

20. What are the primary causes of acid rain?   a. ozone         b. oxides of nitrogen and sulfur

c. hydrogen               d. helium

21. Where do the gases which cause acid rain come from?    (Select all correct)

a. automobile and truck exhausts             b. electric power plants that burn oil and coal

c. homes and factories that heat with oil and natural gas         d. chlorofluorocarbons

22. Even if there were no danger of radioactive materials contaminating the environment from the operation of nuclear power plants, what would be their greatest drawback?

a. they produce CO₂                        

b. they produce radioactive wastes that remain dangerous for thousands of years

c. they produce oxides of nitrogen and sulfur that cause depletion of ozone

23. Which of the following are threats to the populations of fish that humans currently use for food?  (select all correct).        a. pollution of rivers caused by sewage, farm fertilizer, and animal waste

b. global warming that threatens coral reefs that in turn support many fish “nurseries”

c. overharvesting of fish                  

d. acidification of the oceans caused by oceanic absorption of carbon dioxide from the atmosphere

24. Which of the following biomes is characterized by the highest diversity of species?

a. Temperate deciduous forests                b. tropical rain forests          c. tundra        d. taiga

25. Which of the following biomes has trees that seasonally shed their leaves?

a. Temperate deciduous forests                b. tropical rain forests          c. tundra        

d. taiga (northern coniferous forest)

26. What is a distinguishing feature of the tundra?        a. Wind-pollinated grasses

b. infertile soil            c. year-round ice cover                   

d. permafrost: a layer of permanently frozen soil beneath the surface

27.  Which of the following release carbon dioxide into the atmosphere? (select all correct)

a. photosynthesis                 b. respiration by animals                 

c. respiration by decomposers such as bacteria and fungi

d. clearing of tropical forests                      e. burning of oil, coal, gasoline, and methane (“natural gas”)

28. How much warmer is the earth’s atmosphere today compared to the average temperature in 1961-1990?

a. 0.1 degrees C (=0.18 degrees Fahrenheit)                 b. 0.4 degrees C (= 0.7 degrees Fahrenheit)

c. 0.6 degrees C (= 1.1 degrees Fahrenheit)                  d. 0.8 degrees C (=1.44 degrees Fahrenheit)

29. At what time in the past 22,000 years has the temperature of the earth’s atmosphere increased as rapidly as it is increasing now?  (circle all correct)

a. When the volcano erupted in Oregon that created Crater Lake in 5300 BCE

b. During World War I when so many bombs were dropped

c. During World War II when even more bombs were dropped

d. The temperature of the earth has never increased as rapidly as it is now increasing

30. How could society prevent extreme global warming caused by the increase of carbon dioxide in the atmosphere? (select all correct)          a. Stop burning coal            b. stop burning oil and gasoline

c. stop burning “natural” gas (methane).       d. massively increase production of energy through solar, wind, and other renewable sources.          e. stop the destruction of forests and plant new forests

Answer 1

1) exponential growth
2) no, because resources are not unlimited
3) 10,000 years
4) 100 years   
5) 10-12 year
6) 7-8 billion
7) carrying capacity of an ecosystem is the size of the population that can be supported indefinitely upon the available resources and services of that ecosystem
8) over many decades, a more complex food web will develop, compared to the food web in the first few years after clearing the land
9) more soil erosion b. more carbon dioxide released into the atmosphere
c. loss of species diversity d. increased instability of the earth’s ecosystems
10) burning of fossil fuels b. clearing of forest land
11) global warming
12) flooding of coastal areas
c. climate change leading to unpredictability in crop production
13) A) increase in CFC gas in atmosphere
13) B) increased skin cancer   
c. climate change leading to unpredictability in crop production   
14) mexico
15) (d) and (c)
16) manual transmission
17) the world population would stop growing in 20-30 years
18) . the world population might go so far over the carrying capacity that the population would fall rapidly, with the loss of hundreds of millions of human lives from malnourishment and disease

19) the continued increase in the human population will require switching to renewable sources of energy and recycling of most of the products we use
c. significant changes in our economic systems would be required

20) oxides of nitrogen and sulfur
21) automobile and truck exhausts b. electric power plants that burn oil and coal
22) they produce radioactive wastes that remain dangerous for thousands of years
23) pollution of rivers caused by sewage, farm fertilizer, and animal waste

24)tropical rain forests
25)Temperate deciduous forests
26) . permafrost: a layer of permanently frozen soil beneath the surface
27) respiration by animals   
c. respiration by decomposers such as bacteria and fungi
28) 0.8 degrees C (=1.44 degrees Fahrenheit)
29) The temperature of the earth has never increased as rapidly as it is now increasing
30) Stop burning coal b. stop burning oil and gasoline
massively increase production of energy through solar, wind, and other renewable sources. e. stop the destruction of forests and plant new forests