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Ecology Cycles

Total questions: 25

Worksheet time: 25mins

Name
Class
Date
1.

Which process takes carbon dioxide out of the atmosphere?

a)

respiration

b)

combustion

c)

decomposition

d)

photosynthesis

2.

What is the process of taking nitrogen gas from the atmosphere and converting it to usable compounds?

a)

nitrogen composition

b)

ammonia

c)

nitrogen fixation

d)

denitrification

3.

Which of the following would be the definition of a detritivore/decomposer?

a)

Animals that eat insects.

b)

Organisms that feed on rocks, recycling the nutrients back into the ground.

c)

Organisms that eat only plants

d)

Organisms that feed on dead or decaying organisms

4.

Which describes the relationship between plants and animals in the carbon cycle?

a)

Plants produce and release oxygen that animals need

b)

Plants produce and release carbon dioxide that animals need

c)

Animals produce and release oxygen that plants need

d)

Animals produce oxygen that plants turn into carbon dioxide

5.

Which organisms convert nitrogen gas into a usable form for plants and animals?

a)

bacteria

b)

animals

c)

fungi

d)

car exhaust

6.

The amount of energy transferred from a lower trophic level to the next highest level is roughly about _____.

a)

1%

b)

10%

c)

100%

d)

1000%

7.

Which organisms are the first to use the sun's energy to produce carbohydrates?

a)

consumers

b)

detritivores

c)

producers

d)

decomposers

8.

Which role do the rats and insects inhabit in the food web above?

a)

primary consumer

b)

secondary consumer

c)

producer

d)

decomposer

9.

After a forest fire, an ecosystem would start regrowth through -

a)

primary succession

b)

secondary succession

c)

climax community

d)

limiting factors

10.

Breaking News! A new island has formed off of Hawaii! What must occur for it to become an ecosystem?

a)

Secondary Succession

b)

Aquatic succession

c)

Primary Succession

d)

Ferns must grow

11.

Which of the following would provide the MOST energy in an ecosystem?

a)

Producers

b)

Herbivore

c)

Omnivore

d)

Carnivore

12.

Humans are disrupting the carbon cycle in ways that have resulted in increased levels of carbon dioxide in our atmosphere. Which of the following human activities are most directly responsible for this increase?

a)

Deforestation and the clearing of plants that absorb carbon dioxide through photosynthesis.

b)

The addition of larger amounts of carbon dioxide into the atmosphere by burning fossil fuels (coal, oil, natural gas).

c)

The production of cement.

d)

I and III only

e)

I, II and III

13.

Which of the following statements about the carbon cycle is true?

a)

Carbon transfer from photosynthesis is in a steady state with respiration and decomposition.

b)

The majority of dead biomass is accumulated in sedimentation.

c)

Combustion of carbon is equivalent in mass to sedimentation.

d)

Most of the carbon entering the oceans is from terrestrial ecosystems.

e)

Carbon exchange between the atmosphere and terrestrial ecosystems is primarily an abiotic process.

14.

The nitrogen cycle is unique in that atmospheric nitrogen cannot be converted directly by organisms into usable nitrogen. What is necessary in order for atmospheric nitrogen to be converted to a usable form of nitrogen by organisms?

a)

Ammonification

b)

Denitrifying bacteria

c)

Nitrifying bacteria

d)

Decomposition

e)

Nitrogen fixation

15.

In which stage of the nitrogen cycle do soil bacteria convert ammonium ions (NH4+) into nitrate ions (NO3-); a form of nitrogen that can be used by plants?

a)

Nitrogen fixation

b)

Nitrification

c)

Assimilation

d)

Ammonification

e)

Denitrification

16.

A food chain is illustrated below:

The wavy arrows most likely represent

a)

Energy released from metabolism into the environment as heat.

b)

Oxygen released from metabolism produced by cellular respiration.

c)

The absorption of energy from the environment that has been created.

d)

The transport of glucose away from the organism through photosynthesis.

17.

The release of this element into the atmosphere is due, in large part, to fossil fuel combustion and deforestation.

a)

Sulfur

b)

Nitrogen

c)

Carbon

d)

Phosphorus

e)

All of the above cycles.

18.

Which of the following has shifted the storage of carbon from sediment to the atmosphere?

a)

Mining of coal

b)

Combustion of fossil fuels

c)

Increased occurrence of acid precipitation

d)

Extraction of crude oil

e)

Industrial smog

19.

In the oceans, upwellings occur when large volumes of water from great depths come up to the surface bringing nutrients with it. Upwelling, therefore, generate

a)

High biotic potential

b)

Low primary productivity of marine algae

c)

High primary productivity of marine algae

d)

Nutrient poor waters

e)

Strong currents

20.

Which element is consumed during decomposition in and aquatic environment, potentially leading to a hypoxic (low oxygen) situation?

a)

Nitrogen

b)

Phosphorus

c)

Calcium

d)

Carbon

e)

Oxygen

21.

Using the graph, which of the following is the most likely cause of the recent trend noted for all three gases?

a)

Increased burning of wood and biomass for fuel

b)

Increasing number of livestock being raised

c)

Increased combustion of fossil fuels

d)

Global climate change

e)

More materials being disposed of in landfills

22.

Which of the following processes is primarily responsible for returning carbon dioxide to the atmosphere in the carbon cycle?

a)

Photosynthesis

b)

Respiration

c)

Nitrification

d)

Assimilation

23.

In the nitrogen cycle, which process involves the conversion of nitrogen gas (N2) into ammonia (NH3) by bacteria?

a)

Nitrification

b)

Denitrification

c)

Nitrogen fixation

d)

Ammonification

24.

What role do decomposers play in the nutrient cycles within an ecosystem?

a)

They convert solar energy into chemical energy.

b)

They fix atmospheric nitrogen into a usable form.

c)

They break down dead organisms, returning nutrients to the soil.

d)

They absorb carbon dioxide during photosynthesis.

25.

Which of the following best describes the water cycle's role in regulating Earth's climate?

a)

It transports nutrients from the soil to plants.

b)

It distributes heat around the planet through ocean currents.

c)

It converts carbon dioxide into oxygen.

d)

It fixes nitrogen into the soil.