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Chapter 7 Unit Study Guide



Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
 

 1. 

Many large cities grew up on rivers or coasts because people used the water for
a.
agriculture.
b.
household uses.
c.
transportation.
d.
recreation.
 

 2. 

Plants use water to make food in a process called
a.
irrigation.
b.
agriculture.
c.
photosynthesis.
d.
groundwater.
 

 3. 

Approximately what percentage of Earth's water is fresh water?
a.
97 percent
b.
71 percent
c.
30 percent
d.
3 percent
 

 4. 

Most of Earth's fresh water is found in
a.
huge masses of ice near the North and South Poles.
b.
cracks and spaces in underground soil and rock.
c.
the oceans.
d.
rivers and lakes.
 

 5. 

The process by which molecules at the surface of a liquid absorb enough energy to change into a gas is called
a.
transpiration.
b.
evaporation.
c.
condensation.
d.
precipitation
 

 6. 

The process by which plants release water into the air is called
a.
precipitation.
b.
condensation.
c.
evaporation.
d.
transpiration.
 

 7. 

Water that falls to Earth as rain, snow, sleet, or hail is called
a.
condensation.
b.
evaporation.
c.
precipitation.
d.
transpiration.
 

 8. 

If you let your hair air-dry after going swimming, you are taking advantage of
a.
evaporation.
b.
condensation.
c.
melting.
d.
freezing.
 

 9. 

In order to move from the ocean to the atmosphere, a water molecule must
a.
release energy.
b.
absorb energy.
c.
condense.
d.
transpire.
 

 10. 

The total amount of water on Earth
a.
is increasing.
b.
is fairly constant.
c.
is decreasing.
d.
depends on the weather.
 

 11. 

The land area that supplies water to a river system is called a
a.
watershed.
b.
tributary.
c.
divide.
d.
stream.
 

 12. 

The natural deposits that help keep rivers from flooding are called
a.
levees.
b.
divides.
c.
tributaries
d.
watersheds.
 

 13. 

Which of the following could cause a river to flood?
a.
colder than normal spring temperatures
b.
a period of less rain than usual in an area
c.
an increased volume of water entering the river channel
d.
natural levees forming alongside the river
 

 14. 

A lake can be formed in all the following ways EXCEPT by
a.
water collecting in a hollow left by melting ice.
b.
water filling the crater of a volcano.
c.
a dam blocking the flow of a river.
d.
water flowing quickly through a narrow channel.
 

 15. 

A lake that stores water for human use is called a
a.
reservoir.
b.
wetland
c.
watershed.
d.
pond.
 

 16. 

A green film of algae in a fish tank is an example of the early stages of
a.
lake turnover.
b.
eutrophication.
c.
precipitation.
d.
flooding.
 

 17. 

What seasonal change refreshes the supply of nutrients throughout a lake?
a.
precipitation
b.
flooding
c.
lake turnover
d.
eutrophication
 

 18. 

Materials that allow water to easily pass through them are
a.
permeable.
b.
impermeable.
c.
saturated.
d.
unsaturated.
 

 19. 

People can obtain groundwater by drilling a well
a.
above the water table.
b.
into an aquifer.
c.
into the unsaturated zone.
d.
into the impermeable layer.
 

 20. 

New water that enters an aquifer from the surface is called
a.
recharge.
b.
a spring.
c.
an artesian well.
d.
a geyser.
 

 21. 

A well in which groundwater rises because of pressure is called a(n)
a.
artesian well.
b.
water table.
c.
geyser.
d.
dry well.
 

 22. 

Which of the following is NOT a type of freshwater wetland?
a.
a marsh
b.
a swamp
c.
a lake
d.
a bog
 

 23. 

Wetlands help control flooding by
a.
absorbing runoff from heavy rains.
b.
collecting water behind dams.
c.
providing natural water filtration.
d.
quickly releasing water.
 

Modified True/False
Indicate whether the sentence or statement is true or false.  If false, change the identified word or phrase to make the sentence or statement true.
 

 24. 

Most of Earth's water is found in lakes and rivers. _________________________

 

 25. 

Sources of salt water on Earth include ice, rivers, lakes, and groundwater. _________________________

 

 26. 

Clouds form when water vapor in the atmosphere condenses into water droplets. _________________________

 

 27. 

The land area that supplies water to a river system is called a divide. _________________________

 

 28. 

Natural sediment deposits called dams help keep rivers inside their banks. _________________________

 

 29. 

Water moves easily through impermeable materials. _________________________

 

Completion
Complete each sentence or statement.
 

 30. 

Most of Earth's fresh water is in the form of ____________________.
 

 

 31. 

Fresh water found in soil and rock layers below Earth's surface is called ____________________.
 

 

 32. 

Most water in Earth's atmosphere is in the gaseous form, called _________________________.
 

 

 33. 

Water moves from the atmosphere to Earth's surface as rain, snow, and other forms of ____________________.
 

 

 34. 

The _________________________ is the continuous process by which water moves through the living and nonliving parts of the environment.
 

 

 35. 

The energy for the water cycle originally comes from the ____________________.
 

 

 36. 

Wetlands help prevent ____________________ by absorbing runoff from heavy rains.
 

 

 37. 

A body of standing water that is deep enough that sunlight does not reach the bottom is called a(n) ____________________.
 

 

 38. 

A seasonal change called _________________________ refreshes the supply of nutrients throughout a lake.
 

 

 39. 

Over many years, the levels of nutrients in a lake build up in the process of ____________________.
 

 

 40. 

An area of land that is covered with a shallow layer of water during some or all of the year is called a ____________________.
 

 

 41. 

A ridge of land that separates two watersheds is called a ____________________.
 

 

 42. 

The area of soil in which the pores are totally filled with water is called the ____________________ zone.
 

 

 43. 

The top of the saturated zone is called the _________________________.
 

 

 44. 

People do not have to use a pump to obtain water from a(n) ____________________ well.
 

 

Short Answer
 
 
chapter_7_study_gui_files/i0490000.jpg
 

 45. 

Which well(s) end in a saturated zone?
 

 46. 

Which well(s) end in an unsaturated zone?
 

 47. 

Which well(s) will not provide water? Explain why not.
 
 
chapter_7_study_gui_files/i0530000.jpg
 

 48. 

What percentage of Earth's total water is fresh water?
 

 49. 

Which portions of the fresh water circle graph include water that is available for human use?
 

 50. 

Why is most of Earth's water not useful for drinking or irrigation?
 

Essay  (Extra Credit - 5 points each)
 

 51. 

Explain why Earth is often called the "water planet" and why it might be more accurate to call it the "saltwater planet."
 

 52. 

A community is considering draining nearby wetlands to make room for new construction. Give two reasons the wetlands might be worth preserving.
 



 
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