WorksheetsCarbon Cycle
Total questions: 15
Worksheet time: 15mins
When humans burn fossil fuels, most of the carbon quickly enters the _______________________ as carbon dioxide.
Water
Atmosphere
Sun
Ground
Carbon enters the soil through dead plant or animal matter.
Decomposition
Respiration
Photosynthesis
Diffusion
How do plants affect the air that animals and people breathe?
Plants use oxygen from the air to make their own food
Plants release pollution into the air
Plants take in carbon dioxide and release oxygen
Plants take in oxygen and release carbon dioxide
In the carbon cycle, animals can release carbon back into the cycle through __________ or through __________.
burning . . . photosynthesis
fixation . . . decomposition
decomposition . . . photosynthesis
respiration . . . decomposition
respiration . . . photosynthesis
How does the carbon in grass become part of a lion?
The lion eats the grass
Carbon from grass doesn't end up in a lion.
The carbon ends up in the lion's food chain.
The lion breathes in carbon given out by the plant
If the plant population decreased, the amount of carbon dioxide in the atmosphere would _________.
Stay the same
Increase
Decrease
How does the human body return carbon to the atmosphere in the carbon cycle?
Waste products
Photosynthesis
Cellular respiration
Formation of glucose
If a forest fire occurs, what will happen to the carbon in the forest?
It will go into the soil
It will go into the atmosphere
It will runoff into nearby streams and rivers
It will be destroyed
Where does all the carbon in organisms (living things) originate from?
Earth's atmosphere
Rocks
Water
Soil
What kind of organism takes out the most carbon from the atmosphere?
Plants
Bacteria
Animals
Humans
Check all the ways that carbon dioxide is ADDED to the atmosphere.
Respiration
Combustion
Photosynthesis
Diffusion
Decomposition
Check all the ways that carbon dioxide is REMOVED from the atmosphere.
Respiration
Combustion
Photosynthesis
Diffusion
Decomposition
What is the primary process by which carbon is removed from the atmosphere and incorporated into organic molecules?
Photosynthesis
Respiration
Combustion
Decomposition
Which of the following is a major carbon sink that absorbs more carbon than it releases?
Oceans
Volcanoes
Fossil fuels
Atmosphere
In the carbon cycle, what role do decomposers play in the ecosystem?
They release carbon dioxide back into the atmosphere by breaking down dead organisms.
They convert carbon dioxide into oxygen through photosynthesis.
They store carbon in the form of fossil fuels.
They absorb carbon dioxide from the atmosphere and store it in their tissues.
