Name:_____________________________________________ Date:_________________ Block:____________
Ecology
Biomes and Population Density
A biome is a large geographical area defined by a unique set of abiotic factors – particularly climate – and a
characteristic assemblage of plants and animals. Each biome consists of many ecosystems whose communities
have adapted to the small differences in climate and the environment inside the biome. Below is a list of the
world’s 10 major biomes:




Tropical Rainforest
Tropical Dry Forest
Tropical Savanna
Desert
 Temperate Grassland
 Temperate Woodland
and Shrubland
 Temperate Forest
 Northwestern
Coniferous Forest
 Boreal Forest
 Tundra
Using pages 100-104 of your textbook, answer the following questions:
1.
Which biome is characterized by very low temperatures, little precipitation, and permafrost?
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2. Which two biomes have the least amount of precipitation?_______________________________________
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3. Which biome is characterized by its thin, nutrient-poor soil and dense covering known as a canopy?
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4. Which biomes are characterized by their dominant plants often being drought-tolerant and fireresistant? _________________________________________________________________________________
5. The temperate forest has what type of soil? Explain why you believe the soil is this way for this particular
biome. ____________________________________________________________________________________
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6. Which biome is nicknamed the “temperate rain forest”? ________________________________________
7. Which biome is nicknamed the “taiga”? ________________________________________________________
8. The coniferous forest and boreal forest share similar tree types. Why? ______________________________
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9. What was the average temperature of Chennai, India – located in the tropical dry forest – in December?
What month was this temperature the highest for this location? ___________________________________
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10. In Mombasa, Kenya – a tropical savanna – which month has the highest average precipitation? The
lowest? ____________________________________________________________________________________
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Review of Ecology
11. What is an abiotic factor? ____________________________________________________
12. List 3 examples of abiotic factors.
a.
b.
c.
13. What is a biotic factor? ______________________________________________________________________
14. List 3 examples of biotic factors.
a.
b.
c.
15. What type of growth occurs when individuals in a population reproduce at a constant rate under ideal
conditions? ________________________________________________________________________________
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16. Draw an example of this growth on the graph. Label the x and y axis.
17. Define logistic growth. _______________________________________________________________________
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18. Draw an example of logistic growth on the graph. Label the x and y axis.
19. Of an energy stored in an organism, approximately 10% is passed on to the next tropic level. What
happens to the rest? _________________________________________________________________________
20. Of the following factors, which do you believe does NOT contribute to the Earth’s climate: latitude,
longitude, shape of landmasses, transport of heat? ________________________________________________
21. Describe symbiosis. _________________________________________________________________________
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22. Describe commensalism. ___________________________________________________________________
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23. Describe parasitism. ________________________________________________________________________
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Population Density and Limiting Factors
Read pages 119-132 of your book. Once finished, complete the following questions about populations.
24. What are 3 important characteristics of a population?
a.
b.
c.
25. Define population density. ____________________________________________________________________
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26. What is immigration? ______________________________________________________________________
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27. What is emigration? ________________________________________________________________________
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28. Define density-dependent limiting factor _______________________________________________________
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29. Give 3 examples density-dependent factors.
a.
b.
c.
30. Define density-independent factor. ____________________________________________________________
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31. Give 3 examples of density-independent factors.
a.
b.
c.
32. What is demography? _______________________________________________________________________
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33. Explain demographic transition. _____________________________________________________________
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34. In 1990, what was the human population? ______________________________________________________
35. In 2050, what is the anticipated human population? ______________________________________________
36. What two years had the highest growth rate? The lowest? _________________________________________
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Isle Royal
The wolves and moose of Isle Royale, Michigan have been studied for more than five decades. This
research represents the longest continuous study of any predator-prey system in the world.
The most important events in
the chronology have been essentially
unpredictable. In 1980 the wolf
population crashed when humans
inadvertently introduced a disease,
canine-parvovirus. In 1996, the moose
population collapsed during the most
severe winter on record, leaving them
with a food shortage. In the late 1990s,
intense levels of inbreeding among
wolves were mitigated when a wolf
immigrated from Canada. In response,
the wolf population generally
increased throughout the early 21st
century, despite declining moose
abundance.
37. In what year was the moose population the highest? The lowest? __________________________________
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38. In what year was the wolf population the highest? The lowest? _____________________________________
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39. Why did the wolf population decrease drastically around 1980? ____________________________________
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40. Give one explanation as to why the moose population increased drastically around 1994-1995. __________
___________________________________________________________________________________________
41. The year that the moose population was highest, what was the approximate
number of moose in the population? _______________________________________________