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Nitrogen cycle

Total questions: 50

Worksheet time: 25mins

Name
Class
Date
1.

Which nitrogen cycle process is occurring when bacteria convert ammonium to nitrite and then into nitrate?

a)

nitrogen fixation

b)

nitrification

c)

denitrification

d)

ammonification

e)

assimilation

2.

Which of these nitrogen cycle processes converts atmospheric nitrogen to a soil form of nitrogen that is usable by plants?

a)

nitrogen fixation

b)

nitrification

c)

denitrification

d)

ammonification

e)

assimilation

3.
How much of the atmosphere is composed of nitrogen gas?
a)
87%
b)
38%
c)
78%
d)
21%
4.
Organisms that break down dead plants & animals and release nitrogen back into atmosphere...
a)
bacteria
b)
plants
c)
animals
d)
producers
5.
Organisms that need nitrogen to survive
a)
only plants
b)
only animals
c)
only bacteria
d)
all living organisms
6.
Plants and animals cannot use nitrogen directly from the air.
a)
True
b)
False
7.
After plants and animals contain nitrogen, what puts it back into atmosphere and soil?
a)
decomposition
b)
precipitation
c)
condensation
d)
bacteria
8.
Nitrification happens in the ______
a)
Air 
b)
Soil 
c)
Ground Water 
d)
Plants 
9.

What is true about nutrients in the ecosystem (such as water, carbon, and nitrogen)?

a)

They are not affected by humans in the ecosystem.

b)

They cannot be recovered if they are lost in the ecosystem.

c)

They cycle through the ecosystem in different forms to support life.

d)

They are usually only found in one form in the ecosystem to support life.

10.

What is the chemical equation for photosynthesis?

a)

Sun+water+co2=o2+sugar

b)

sun+photosynthesis

c)

O2+sugar=water+co2+energy

11.

what is the equation for respiration

a)

Something

b)

What’s respiration

c)

o2+sugar=water+co2+energy

d)

Sun+water+co2+energy

12.

How do humans influence the carbon cycle?

a)

Burning fossil fuels

b)

Farting

c)

Crash bandicoot nitrocart

d)

Gex

13.

The process of turning ammonia(NH3) into ammonia salts (NH^4+) is called what?

a)

Gex 2 return of the gecko

b)

Carbonization

c)

Fossilization

d)

denitrification

e)

The rein of the ape is no more

14.

How do plants and animals interact in the carbon cycle?

a)

They eat plants

b)

They eat animals

c)

They eat captain crunch

d)

Time travel

15.

Why is combustion an important process in the carbon cycle?

a)

It turns fossil fuels into carbon dioxide.

b)

It turns once living things and organic matter into fossil fuels.

c)

It turns carbon dioxide into glucose, so animals can eat the carbon.

d)

It turns glucose into carbon dioxide, which gets released into the air.

16.

What is true about nutrients in the ecosystem (such as water, carbon, and nitrogen)?

a)

They are not affected by humans in the ecosystem.

b)

They cannot be recovered if they are lost in the ecosystem.

c)

They cycle through the ecosystem in different forms to support life.

d)

They are usually only found in one form in the ecosystem to support life.

17.

Why is decomposition an important process in the carbon cycle?

a)

It turns fossil fuels into carbon dioxide.

b)

It turns once living things and organic matter into fossil fuels.

c)

It turns carbon dioxide into glucose, so animals can eat the carbon.

d)

It turns glucose into carbon dioxide, which gets released into the air.

18.

Why is respiration an important process in the carbon cycle?

a)

It turns fossil fuels into carbon dioxide.

b)

It turns once living things and organic matter into fossil fuels.

c)

It turns carbon dioxide into glucose, so animals can eat the carbon.

d)

It turns glucose into carbon dioxide, which gets released into the air.

19.

Why is photosynthesis an important process in the carbon cycle?

a)

It turns fossil fuels into carbon dioxide.

b)

It turns once living things and organic matter into fossil fuels.

c)

It turns carbon dioxide into glucose, so animals can eat the carbon.

20.

How does a lion obtain the carbon it needs from a grass plant?

a)

The lion breathes in carbon given off by the grass.

b)

The lion cannot obtain the carbon in a grass plant.

c)

The lion absorbs the carbon given off by transpiration.

d)

The lion eats the antelope that ate the grass.

21.

Within the carbon cycle, anything that absorbs more carbon from the atmosphere than it releases.

a)

carbon sink

b)

carbon source

22.

Within the carbon cycle, anything that releases more carbon into the atmosphere than it absorbs.

a)

carbon sink

b)

carbon source

23.

Carbon can be released into the atmosphere by...

a)

Cell respiration in plants and animals on land

b)

Combustion of fossil fuels

c)

Cell respiration in plants and animals in the ocean

d)

Photosynthesis

24.

What is the process in which dead plants and animals become fossil fuels?

a)

Respiration

b)

Photosynthesis

c)

Combustion

d)

Decomposition

25.

What converts nitrogen gas into a usable form for plants and animals?

a)

bacteria

b)

rain

c)

fungi

d)

car exhaust

26.

According to this diagram, plants use nitrogen to make _________________________

a)

carbohydrates

b)

cellulose

c)

proteins

d)

unsaturated fats

27.

According to this diagram, what turns atmospheric nitrogen into NH3NH_3  ?

a)

nitrogen fixing bacteria

b)

plants

c)

denitrifying bacteria

d)

animals

28.

Which of the following is true about nitrifying bacteria?

a)

They turn ammonium into Nitrates and Nitrites.

b)

They come from animal waste.

c)

They do the process of denitrification.

d)

It comes from lightning.

29.

How does nitrogen get into the soil in the first place? Select all that apply.

a)

Animal waste

b)

Lightning

c)

Dead and decaying organisms

d)

Photosynthesis

30.

Burning fossil fuels lead to ____________

a)

Greenhouse effect

b)

Cleaner air

c)

Less humidity

d)

Nuclear energy

31.

Nitrogen goes through the process of ________ to become plant use. 

a)

Transformation

b)

Transpiration

c)

Denitrification

d)

Fixation

32.
The process of plants losing water through their leaves is called ____.
a)
condensation
b)
evaporation
c)
transpiration
d)
exhaling
33.
What is the only process that removes carbon from the atmosphere?
a)
combustion
b)
cellular respiration
c)
photosynthesis
d)
decomposition
34.
Where is carbon stored in the environment?
a)
Fossil fuels
b)
Wood of trees
c)
Calcium carbonate (shells and bones)
d)
All of the above
35.

A particular golf course is using large amounts of nitrogen fertilizer. What process could move this nitrogen into a local stream?

a)

volatilization

b)

nitrogen fixation

c)

runoff and leaching

d)

ammonification

36.

What is the largest reservoir for nitrogen?

a)

the ocean

b)

rocks and minerals

c)

the atmosphere

d)

bacteria

37.
Carbon dioxide is added to the atmosphere by
a)
Burning fossil fuels 
b)
Cellular respiration
c)
Decomposing organic matter
d)
All answers are correct
38.

In an ecosystem, what happens to the atoms of certain chemical elements, such as carbon, oxygen, and nitrogen?

a)

They move into and out of living systems.

b)

They are only found in abiotic factors.

c)

They move out of living systems and do not return.

d)

They move into living systems and remain there.

39.

The water cycle is driven by

a)

water

b)

wind

c)

the sun

d)

Earth's rotation

40.

According to the diagram, geologic activity, such as volcanoes,

a)

Increases the levels of CO2 in the atmosphere.

b)

Decreases the levels of CO2 in the atmosphere.

41.

Nitrogen in the atmosphere is unusable. What form is nitrogen in the atmosphere?

a)

Nitrites

b)

Ammonia

c)

Nitrates

d)

N2 gas

42.

Denitrifying bacteria

a)

Turn nitrogen gas into nitrates so that plants can synthesize amino acids.

b)

Turn nitrates into nitrites so that nitrogen fixing bacteria can synthesize DNA.

c)

Returns nitrogen into the atmosphere in the form of N2 gas.

d)

Use phosphorus as fertilizer.

43.
How do living organisms return carbon to the atmosphere in the carbon cycle?
a)
respiration and photosynthesis
b)
 decomposition and respiration
44.
Identify the cycle pictured.
a)
The Water cycle
b)
The Carbon cycle
c)
The Nitrogen cycle
d)
The Phosphorus cycle
45.
How does carbon dioxide leave the atmosphere and become part of the food chain?
a)
Through transpiration
b)
Through photosynthesis
c)
Through factory emission
d)
Sunlight
46.

A correct path that nitrogen could take would be

a)

air -> animals -> plants -> bacteria

b)

animals -> air -> bacteria -> plants

c)

bacteria -> air -> plants -> animals

d)

air -> bacteria -> plants -> animals

47.

Decomposition is part of all cycles except _______

a)

the carbon cycle

b)

the nitrogen cycle

c)

the water cycle

d)

the phosphorus cycle

48.

An Aquifer is

a)

porous rock that allows water to flow through it

b)

water that flows through and collects in rock pores

c)

water that soaks into the ground

49.

Infiltration is

a)

porous rock that allows water to flow through it

b)

water that flows through and collects in rock pores

c)

water that soaks into the ground

50.

Which of the following is correct about the carbon cycle?

a)

Photosynthesis of plant life is one of the main producers of CO2

b)

Burning fossil fuels decreases atmospheric CO2

c)

Glucose is a form of carbon storage in plants

d)

Cellular respiration is a process that decreases CO2