Name ______________________________________ Date _________
TEKS Review
4.7C
TEKS 4.7C identify and classify Earth’s renewable resources, including air, plants, water, and
animals; and nonrenewable resources, including coal, oil, and natural gas; and the importance of
conservation
Conservation and Resources
Natural Resources
You depend on natural resources every
day. You breathe in air, you drink water, and
you eat food that was grown in soil. The
clothing you wear, your books, and your home
are all made with natural resources. Even the
resources we use to produce energy are natural
resources. Life on Earth would not be possible
without natural resources.
Renewable Resources
Some resources are reusable. One
example is water, a resource that is essential
for life. All the water we use is part of the
water cycle. This cycle makes water usable
again and again. Air is also reusable. Like
water, it is a renewable resource. A renewable
resource is a resource that can be replaced
within a human lifetime. Renewable resources
can be used again and again—if we use them
carefully.
Many renewable resources come
from farms. Crops such as corn
and wheat must be planted each
year. Many fruits grow on trees
that bloom each
year in orchards.
Air, water, plants, and animals are
renewable resources. The food we eat comes
from plants and animals grown on farms. Each
year, farmers plant new crops in their fields so
we don’t run out of food. New animals are
born to replace ones that die or that are used
for food. Like water in the water cycle, air is
part of a cycle too. The carbon dioxide—
oxygen cycle ensures we always have access
to the oxygen we need from the air.
We must care for renewable resources
even though they can be replaced. For
example, if air and water are polluted, they
must be cleaned before people can use them.
Other renewable resources can be spoiled by
things such as overgrazing, deforestation,
overfishing, and habitat destruction.
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TEKS Review
4.7C
Nonrenewable Resources
Energy Sources
Unfortunately, many resources can be
used only once. A nonrenewable resource is
a resource that cannot be replaced in a human
lifetime. For example, rich soils that are good
for growing crops take thousands of years to
form. If we remove soil from land or allow it
to erode from farms, it cannot be easily
replaced.
Many natural resources are used to
produce energy. Like all resources, some
energy sources are renewable and some are
nonrenewable.
Minerals, as well as metals, are
nonrenewable, too. They occur in limited
amounts in Earth’s crust. Once these resources
are used up, there will never be any more.
Even some plants are essentially
nonrenewable resources. Trees such as fruit
trees do grow quickly and may be replaced in
a few years. But an old-growth forest contains
trees that are hundreds of years old. Once
these trees are cut down, they will not be
replaced for hundreds of years to come.
Fossil fuels, which include oil, coal, and
natural gas, are nonrenewable energy
resources. These are resources that cannot be
made again in a reasonable amount of time
and will someday be used up. Fossils fuels
form over millions of years from the remains
of dead plants buried beneath Earth’s surface.
In many cases, using nonrenewable
resources has ill effects on the environment.
The burning of fossil fuels cause acid rain and
have also been linked to global warming.
People continue to use fossil fuels, though,
because they are affordable and because the
technologies to use them have been in use for
many years.
As the world begins to run out of fossil
fuels, though, their prices will get higher and
higher. In time, people will not be able to
afford them. However, people will still need a
supply of energy to run their homes,
businesses, schools, and automobiles.
Scientists and engineers will need to develop
alternative energy sources that are renewable.
Renewable energy sources can be used
again and again. Examples of renewable
resources include flowing water, wind, heat
from deep within Earth, solar energy, and
fuels made from plant and animal products.
Oil is a nonrenewable resource and a fossil
fuel. We use drills to reach oil, which
formed underground over millions of years.
Once we use all the oil on Earth, there will
be no more available.
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TEKS 4.7C
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Name ______________________________________ Date _________
Conservation
We can make natural resources last longer
by practicing conservation. Conservation is
the work of protecting and managing our
natural resources. There are three important
ways to conserve resources—reducing how
much you use, reusing resources, and
recycling resources.
Conservationists are people who work to
preserve things in nature. Some work to
protect wild animals or plants, and others
work to protect the habitats of plants and
animals for the future. Some care for wild
places, such as deserts or wetlands. Others
make sure we have clean air and water,
minerals, soil for farming, and trees for
lumber. Still others do scientific research or
work with governments or companies.
Recycling
In recycling, materials that would
otherwise be thrown away are broken down to
be made into new items. For example, when
cans are recycled, they are melted. The melted
metal can be poured into new molds to make
new cans or other metal products.
TEKS Review
4.7C
Recycling helps sustain the environment
for future generations. It helps decrease the
amount of harmful gases that are released into
the atmosphere, and it conserves natural
resources such as timber, water, and minerals.
Reducing and Reusing
When you reuse items, you use items
again that might have been thrown out. For
example, if you reuse plastic food containers,
fewer resources are needed to make new
containers. You can also take reusable bags
with you when you shop so you don’t have to
use new bags each time you go to the store.
One of the easiest ways to conserve
resources is to reduce, or lower, the amount of
a resource you use. Appliances such as air
conditioners, water heaters, and clothes dryers
use a lot of electricity. When you use
appliances less, you are helping to conserve
energy resources. Make sure you always turn
off appliances and lights you are not using.
You can also make sure you do not waste
food. Even though food resources are
renewable, it requires a lot of time and energy
to make and deliver food. Wasting food
wastes many kinds of resources.
Recycling cuts down on the amount of
waste that enters our landfills. Recycling also
saves money and energy. It is much cheaper to
make a new soda can by recycling old ones
than it is to mine and process the ores from the
ground.
Recycling can be done with many kinds
of materials that can be collected, sorted, and
processed into raw materials. Many recycled
products, such as glass, can be recycled again
and again. Paper, though, can be recycled only
a few times. Paper is made of plant fibers that
break down over time.
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TEKS 4.7C
Glass, metals, paper, and many
kinds of plastic can be recycled.
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TEKS Review
4.7C
Materials
Hands-On Activity
Recycling Paper
You can model the process of recycling paper and make
your own sheets of paper from used paper.
Procedure:
safety goggles
scrap paper
water
laundry starch
plastic container
fork
wire window screen with
taped edges
• newspaper
• rolling pin
•
•
•
•
•
•
•
1. Tear or shred the scrap paper into pieces that are no larger than 2 cm.
2. Add the paper and water to the container. Keep track of how much water you must add to
just cover all the paper. Let the paper soak for a few minutes.
3. Add 16 mL of starch for every 240 mL of water you used. Mix the contents of the
container with the fork for several minutes. Take turns mixing so your arm does not get
tired. Try to make a watery pulp that is smooth, not lumpy.
4. Put one screen flat in the foil pan.
5. Pour the pulp slowly onto the screen. Spread the pulp so it covers the whole screen evenly.
6. Lift the screen and the pulp out of the pan, and put it on a pile of newspaper.
7. Put the other screen on top, then add another layer of newspaper.
9. Roll the rolling pin a few times each way, applying pressure.
10. Allow the stack to dry overnight. Remove your paper from the screens, and use it to make
a poster about the importance of conservation.
Discussion Questions:
1. How does recycling paper help conserve resources?
2. Compare your recycled paper to the original scrap paper you used.
How are they alike and different?
3. Do you think it is more important to recycle aluminum cans or paper? Explain.
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TEKS 4.7C
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Name ______________________________________ Date _________
TEKS Review
4.7C
Conservation and Resources
Answer these questions after reading the passage.
Use the Venn diagram below to compare and contrast renewable and nonrenewable resources.
Renewable Resources
Both
Nonrenewable Resources
Why is conservation of resources important?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
List four ways that you can help conserve resources.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
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TEKS 4.7C
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TEKS Review
4.7C
TEKS Assessment 4.7C
Fill in the letter of the best choice.
Which of the following is a
nonrenewable resource?
How many times can an aluminum soda
can be recycled?
It cannot be recycled.
It can be recycled once.
It can be recycled twice.
There is no limit to the number of
times.
Look at the image below.
Which of these processes breaks down
an existing product and uses the
resources obtained to make new
products?
renewing
reusing
Which is the best way for this girl to
practice conservation?
reducing
recycling
Which type of resources cannot be easily
or quickly replaced once they are used?
new
renewable
reusable
nonrenewable
TEKS Review and Assessment
© Houghton Mifflin Harcourt Publishing Company
She could reduce the number of
times she brushes her teeth.
She could reduce the amount of
water she uses by turning off the
faucet.
She could throw away her
toothbrush after each use.
She could use twice as much
toothpaste each time she brushes
her teeth.
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Name ______________________________________ Date _________
TEKS Review
4.7C
Answer Key
Hands-On Activity (p. 4)
1. Recycling paper helps conserve trees. Trees do not need to be cut down when used paper
is recycled and turned into new paper.
2. Answers will vary. Sample answer: My paper has many colors in it. It is not as sturdy as
the original sheet of paper.
3. Accept all reasonable answers. Some students may point out that aluminum is a
nonrenewable resource. If we throw all our aluminum cans away, we will eventually run
out of aluminum. Paper, on the other hand, comes from trees, which are renewable
resources. Other students may point out the important role trees play in the carbon
dioxide–oxygen cycle, and they may argue against cutting them down to make more
paper.
Student Response Activity (p. 5)
1. Renewable Resources—can be replaced in short periods of time, will not run out if
carefully used and managed to avoid damaging environments; Nonrenewable Resources—
can’t be replaced quickly, will eventually run out; Both—types of natural resources
2. Conservation of resources is important because some types of resources will eventually run
out and because it helps to protect the environment.
3. Sample answers: I can recycle materials at home. I can turn off the lights when I’m not in a
room. I can find ways to reuse materials. I can teach my parents about ways to conserve
energy and other resources.
TEKS Assessment (p. 6)
1. C
2. D
3. D
4. D
5. B
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TEKS 4.7C
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