Nitrogen Cycle

What is the primary reservoir of nitrogen on Earth?

• Soil

• Atmosphere

• Oceans

• Plants

Tags

NGSS.MS-LS2-3

Which process converts atmospheric nitrogen (N₂) into ammonia (NH₃) or ammonium (NH₄⁺)?

• Nitrification

• Denitrification

• Nitrogen fixation

• Ammonification

Which organisms are primarily responsible for nitrogen fixation?

• Fungi

• Viruses

• Bacteria

• Insects

What is the role of Rhizobium bacteria in the nitrogen cycle?

• Convert nitrates into nitrogen gas

• Convert nitrogen gas into ammonia

• Decompose dead organisms

• Absorb nitrogen from the soil

Tags

NGSS.MS-LS2-3

The process by which ammonia (NH₃) is converted into nitrites (NO₂⁻) and then nitrates (NO₃⁻) is called:

• Ammonification

• Nitrification

• Denitrification

• Nitrogen fixation

Tags

NGSS.MS-LS2-3

Nitrification is carried out by which type of organisms?

• Fungi

• Nitrogen-fixing bacteria

• Nitrifying bacteria

• Denitrifying bacteria

Tags

NGSS.MS-LS2-3

What is the primary form of nitrogen that plants absorb from the soil?

• Nitrogen gas (N₂)

• Ammonia (NH₄⁺)

• Nitrous oxide

• Atmospheric nitrogen

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

The process in which decomposers break down dead organisms and waste, releasing ammonia, is called:

• Denitrification

• Ammonification

• Nitrification

• Nitrogen fixation

Tags

NGSS.MS-LS2-3

What process converts nitrates (NO₃⁻) back into nitrogen gas (N₂)?

• Nitrification

• Ammonification

• Denitrification

• Nitrogen fixation

Denitrification is performed by:

• Fungi

• Plants

• Denitrifying bacteria

• Herbivores

Tags

NGSS.MS-LS2-3