The Atmosphere
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Printed: December 2, 2013
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C ONCEPT
Concept 1. The Atmosphere
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The Atmosphere
Lesson 15.1: True or False
Name___________________ Class______________ Date________
Write true if the statement is true or false if the statement is false.
_____ 1. Respiration is more-or-less the reverse of photosynthesis.
_____ 2. The atmosphere is a crucial part of the hydrologic cycle.
_____ 3. The ozone layer in the atmosphere allows complex life forms to live on Earth.
_____ 4. Without the atmosphere, Earth would always have the same temperature.
_____ 5. Warm air can hold less moisture than cooler air.
_____ 6. Particles in the atmosphere include metals and fecal matter.
_____ 7. Particles in the atmosphere are needed for clouds to form.
_____ 8. Gravity has no effect on the gases in Earth’s atmosphere.
_____ 9. Virtually all weather takes place in the lower atmosphere.
_____ 10. Carbon dioxide is the only important greenhouse gas.
Lesson 15.1: Critical Reading
Name___________________ Class______________ Date________
Read this passage based on the text and answer the questions that follow.
Significance of the Atmosphere
Earth’s atmosphere, along with the abundant liquid water at Earth’s surface, are the keys to our planet’s unique place
in the solar system. Much of what makes Earth exceptional depends on the atmosphere. Let’s consider some of the
reasons we are lucky to have an atmosphere.
Atmospheric gases, especially oxygen and carbon dioxide, are extremely important for living organisms. Plants use
carbon dioxide to make food (sugar) by photosynthesis and they release oxygen as a waste product of photosynthesis.
Photosynthesis is responsible for nearly all of the oxygen currently found in the atmosphere. By producing oxygen
and food, plants have made an environment that is favorable for other organisms, including animals. Most organisms
use respiration to break down food for energy. This process uses oxygen from the atmosphere and releases carbon
dioxide as a waste product.
There are three other reasons we are lucky to have the atmosphere.
• A layer of ozone gas in the stratosphere absorbs high-energy ultraviolet (UV) radiation from the sun. This
protects living things on Earth’s surface from these harmful rays. Without ozone for protection, only the
simplest life forms would be able to live on Earth.
• The atmosphere moderates Earth’s climate and makes it more hospitable to living things. Greenhouse gases,
such as carbon dioxide and water vapor, trap heat in the atmosphere. Without these gases, Earth’s temperatures
would be frigid at night and scorching during the day.
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• Gas molecules in the atmosphere transmit sound waves to our ears and allow us to hear. Without the atmosphere, Earth would be a virtually silent place.
Questions
1.
2.
3.
4.
Explain how carbon dioxide and oxygen are used by living organisms.
Why is the ozone layer important to life on Earth?
How does the atmosphere moderate Earth’s temperatures?
How does the atmosphere allow us to hear?
Lesson 15.1: Multiple Choice
Name___________________ Class______________ Date________
Circle the letter of the correct choice.
1. The atmosphere is needed for people to
a.
b.
c.
d.
fly planes.
sail boats.
hear birds sing.
all of the above
2. How does the atmosphere change as altitude increases?
a.
b.
c.
d.
The density of air decreases.
The pressure of air increases.
The percent of oxygen in air decreases.
all of the above
3. Without the atmosphere, Earth would have no
a.
b.
c.
d.
life.
weather.
soil.
all of the above
4. The gas that organisms need for respiration is
a.
b.
c.
d.
carbon dioxide.
water vapor.
oxygen.
ozone.
5. Greenhouse gases include
a.
b.
c.
d.
oxygen.
nitrogen.
ozone.
two of the above
6. The amount of water vapor in the air
a.
b.
c.
d.
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is always constant.
varies by location.
varies by season.
two of the above
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Concept 1. The Atmosphere
Lesson 15.1: Matching
Name___________________ Class______________ Date________
Match each definition with the correct term.
Definitions
_____ 1. important greenhouse gas
_____ 2. elevation above sea level
_____ 3. process in which organisms convert sugar into energy
_____ 4. long-term average weather at a specific place
_____ 5. amount of water vapor in the air
_____ 6. description of the atmosphere at a specific time and place
_____ 7. gas in the atmosphere that absorbs UV radiation
Terms
a. humidity
b. climate
c. altitude
d. respiration
e. carbon dioxide
f. weather
g. ozone
Lesson 15.1: Fill in the Blank
Name___________________ Class______________ Date________
Fill in the blank with the appropriate term.
1.
2.
3.
4.
5.
6.
7.
The thin blanket of gases and tiny particles that surrounds Earth is the __________.
The process of __________ is responsible for nearly all the oxygen in the atmosphere.
The molecule that consists of three oxygen molecules is called __________.
__________ gases trap heat in the atmosphere and help to moderate global temperatures.
The two gases that make up 99 percent of the atmosphere are nitrogen and __________.
Air density __________ as altitude increases.
The force of air pushing against a unit of area is called __________.
Lesson 15.1: Critical Writing
Name___________________ Class______________ Date________
Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences.
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Relate air density and pressure to altitude.
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