03.3 BB

What is the largest reservoir of nitrogen?

• Atmosphere

• Biosphere

• Geosphere

• Hydrosphere

Which process converts nitrogen gas into ammonia?

• Denitrification

• Nitrogen fixation

• Nitrification

• Ammonification

Where can nitrogen-containing substances such as ammonia and nitrate be found?

• Atmosphere

• Soil

• Water

• None of the above

What is the role of bacteria and fungi in the nitrogen cycle?

• Convert ammonia into nitrite and nitrate

• Fix nitrogen gas into ammonia

• Release nitrogen compounds from dead organisms

• Convert nitrates into nitrogen gas

What is the process called when bacteria obtain energy by converting nitrates into nitrogen gas?

• Denitrification

• Nitrogen fixation

• Nitrification

• Ammonification

What did German chemists develop in the early twentieth century to transform nitrogen gas into usable forms?

• Nitrogen fixation

• Denitrification

• Nitrification

• Industrial process

Which nutrient is essential for molecules such as DNA and RNA?

• Carbon

• Oxygen

• Nitrogen

• Phosphorus

Where is inorganic phosphorus found in the geosphere?

• Atmosphere

• Soil

• Water

• Marine environments

Where is dissolved phosphate found in the hydrosphere?

• Atmosphere

• Soil

• Water

• Marine environments

What is the rate at which primary producers create new organic material called?

• Primary productivity

• Nitrogen fixation

• Denitrification

• Nitrification