Carbon and Nitrogen Cycle

The flow of carbon from the biosphere to the atmosphere would be slowed by reducing the

• amount of fertilizer applied to fields.
• number of size of forest fires
• buildup of carbonate rocks
• amount of rain water used for irrigation

Which of the following processes converts C₆H₁₂O₆ to an inorganic molecule CO₂

• translation
• photosynthesis
• cellular respiration
• excretion

Organisms use nitrogen to form

• carbohydrates and lipids
• proteins and lipids
• lipids and nucleic acids
• proteins and nucleic acids

Which of the following describes the role of nitrogen-fixing bacteria in the nitrogen cycle? Nitrogen-fixing bacteria convert

• nitrates intro nitrogen gas
• ammonia into proteins
• nitrogen gas into ammonia
• proteins into nitrates

What is one of the most important processes that removes carbon from the atmosphere? 

• photosynthesis
• cellular respiration
• erosin
• soil respiration

What effect will an increase in ocean phytoplankton have on the carbon cycle?

• more carbon will leave the atmosphere
• more carbon will enter the atmosphere
• less carbon will leave the atmosphere
• less carbon will enter the atmosphere

Animals obtain the nitrogen they need directly from the

• soil in their habitat
• air they breathe
• plants they eat
• bacteria living within them

Growing legumes such as alfalfa or soy beans increases

• denitrification
• nitrogen fixation
• ammonification
• ammonium oxidation

What forms of nitrogen and carbon can be used by plants?

• ammonia and carbon monoxide
• ammonia, nitrates, and carbon dioxide
• nitrites and carbohydrates
• nitrate and carbon monoxide

Which process moves carbon stored in fossil fuel into another carbon reservoir?

• When fossil fuels are burned, carbon enters the atmosphere as carbon dioxide.
• The denitrifying bacteria turns the fossil fuel into carbon dioxide gas.
• Decomposers convert the fossil fuels into greenhouse gases like carbon dioxide.
• The fossil fuels react with the soil to produce carbonates and carbon dioxide.