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Carbon and Nitrogen Cycles

Total questions: 22

Worksheet time: 14mins

Name
Class
Date
1.

According to this diagram, animals get proteins from eating ______________

a)

decomposers

b)

bacteria

c)

plants

d)

sunlight

2.

According to this diagram, plants use nitrogen to make ________

a)

bacteria

b)

proteins

c)

animals

d)

decomposers

3.
When humans burn fossil fuels, most of the carbon quickly enters the                       as carbon dioxide.
a)
Water
b)
Atmosphere
c)
Sun
d)
Air
4.
Which one of these does not add CO2 to the atmosphere?
a)
cooking with gas
b)
planting trees
c)
burning wood
d)
riding in a bus
5.
Organisms that need nitrogen to survive
a)
only plants
b)
only animals
c)
only bacteria
d)
all living organisms
6.

How nitrogen is "fixed" into useable form for plants

a)

only through action of bacteria

b)

only through lightning

c)

through action of bacteria & lightning

d)

through photosynthesis

7.

What part of the carbon cycle is represented by A?

a)

photosynthesis

b)

decomposition

c)

combustion

d)

cellular respiration

8.

What part of the carbon cycle is represented by cow releasing CO2 back into the atmosphere?

a)

photosynthesis

b)

decomposition

c)

respiration

d)

combustion

9.
What is a decomposer?
a)
Organism that makes its own energy
b)
Organism that breaks down dead organisms
c)
Organism that eats other organisms for food & energy
10.
Which of the following removes carbon from the atmosphere?
a)
Combustion
b)
Respiration
c)
Photosynthesis
d)
Death
11.

What process is represented by D?

a)

nitrification

b)

assimilation

c)

decomposition

d)

denitrification

12.

What process of the carbon cycle is represented by 2?

a)

decomposition

b)

respiration

c)

combustion

d)

photosynthesis

13.

Which process in the nitrogen cycle can involve storms and lightning to move nitrogen gas to the soil in precipitation?

a)

nitrification

b)

ammonification

c)

assimilation

d)

nitrogen fixation

14.

Water also comes from plant leaves to the atmosphere through ________________.

a)

Evaporation

b)

Transpiration

c)

Condensation

d)

Precipitation

15.
TRUE or FALSE?
All of the carbon in existence is continually recycled in the carbon cycle.
a)
True
b)
False
16.

The Carbon Cycle is the process of recycling carbon from _________________ to _________________.

a)

Animals to Clouds

b)

The Sun to Plants

c)

Living things to Nonliving Things

17.

Nitrogen moves through _____, ______ and ______.

a)

Clouds, plants and soil

b)

Air, water and animals

c)

Air, water and soil

18.
Which of the following add carbon dioxide to the atmosphere?
a)
volcanoes
b)
combustion of fossil fuels
c)
animal and plant respiration
d)
all of these
19.

Nitrogen fixation...

a)

animals eat the plants and other animals that contain nitrogen and release it through their waste

b)

Bacteria in the soil and lightning in the atmosphere “fix” the nitrogen

c)

Once in the ground, bacteria in the soil also nitrify the nitrogen

d)

plants absorb nitrogen through their roots and return it back to the atmosphere

20.

Denitrification...

a)

animals eat the plants and other animals that contain nitrogen and release it through their waste

b)

Bacteria in the soil and lightning in the atmosphere “fix” the nitrogen

c)

nitrogen is released back into the atmosphere from the animal’s waste or decomposers

d)

plants absorb nitrogen through their roots and return it back to the atmosphere

21.

How does the chemical equation of photosynthesis: 

6CO2 + 6H2O → C6H12O6 + 6O2,  

model that this chemical reaction obeys the Law of Conservation of Matter?

a)

because there are the same number of atoms of each element shown on both sides

b)

because they both start and end with two sets of particles

c)

because they both start and end with diatomic (two-atomed) molecules

d)

because they both start and end with the same types of particles

22.

According to the law of conservation of matter, in any food chain we know that

a)

the amount of matter increases as the food web progresses from the producers to the consumers.

b)

matter is created at the start of a food web and destroyed in the end.

c)

matter is changed into various forms but the total quantity remains unchanged.

d)

the quantity of matter in producers and consumers is always equal.