3/27 Nitrogen and carbon cycles

Multiple Choice

Which type of human impact is shown in the picture below?

• Desertification

• Deforestation

• Urban sprawl

• Land pollution

Multiple Choice

What is the carrying capacity of the following graph?

• 1000
• 8000
• 800
• 600

Multiple Choice

Which of the following would be the most likely effect, if there were a sudden increase in the cricket population?

• There would be a decrease in the small bird population.
• There would be a decrease in the grass/flowers population.
• There would be a decrease in the mice population.
• There would be an increase in the grass/flowers population.

Multiple Choice

Examples of how humans negatively affect local ecosystems are

• Building dams, deforestation (cutting down trees), adding point sources to nearby streams to allow for run-off, building roads and structures, and salting roads.
• Creating laws to prohibit fishing from local streams.
• Planting trees and other plants to attract native species.
• Removing non-native species from the environment.

Multiple Choice

How would the biodiversity of this ecosystem be affected if the lantern fish disappeared?

• The ocean sunfish population would increase.
• The large shark population would die out.
• The squid would die out.
• There would be no change.

Multiple Choice

Which organism do the owl and the weasel compete for in the food web?

• Hawk
• Spider
• Grasshopper
• Shrew

Multiple Choice

How animals get the nitrogen they need

• from the air they breathe
• from the water they drink
• from the food they eat
• from the Sun

Multiple Choice

How nitrogen is "fixed" into useable form for plants

• only through action of bacteria
• only through lightning
• through action of bacteria & lightning
• through photosynthesis

Multiple Choice

Nitrogen rich fertilizers and manure can cause water pollution.

• True
• False

Multiple Choice

A correct path that nitrogen could take would be

• air -> animals -> plants -> bacteria

• animals -> air -> bacteria -> plants

• bacteria -> air -> plants -> animals

• air -> bacteria -> plants -> animals

Multiple Choice

When humans burn fossil fuels, most of the carbon quickly enters the                       as carbon dioxide.

• Water
• Atmosphere
• Sun
• Air

Multiple Choice

Which of the following add carbon dioxide to the atmosphere?

• volcanoes
• combustion of fossil fuels
• animal and plant respiration
• all of these

Multiple Choice

Bacteria fix nitrogen on plant roots. Plant roots provide sugar to bacteria. This is an example of

• mutualism
• parasitism
• commensalism
• competition