Earth's Natural Processes

the first step of the nitrogen cycle when bacteria convert nitrogen gas (N2) from the atmosphere into ammonia (NH3) and other usable forms

• nitrogen fixation

• nitrification

• ammonification

• denitrification

Tags

NGSS.MS-LS2-3

the second step of the nitrogen cycle when decomposers break down waste to form ammonium (NH4) compounds

• nitrogen fixation

• nitrification

• ammonification

• denitrification

Tags

NGSS.MS-LS2-3

the third step of the nitrogen cycle when ammonia is converted to nitrite (NO2), then to nitrate (NO3). The nitrate can then be used by plant

• nitrogen fixation

• nitrification

• ammonification

• denitrification

Tags

NGSS.MS-LS2-3

the fourth step of the nitrogen cycle when bacteria converts nitrate (NO3) back to gaseous nitrogen (N2) in soil or deep ocean waters

• nitrogen fixation

• nitrification

• ammonification

• denitrification

Tags

NGSS.MS-LS2-3

the continuous process where inorganic nitrogen is incorporated into organisms that transform it and eventually return it to the environment as excrement or when an organism dies and decomposes

• nitrogen cycle

• water cycle

• phosphorus cycle

• carbon cycle

Tags

NGSS.MS-LS2-3

Nitrogen gas becomes converted into biologically usable chemical forms by what type of organism?

• ammonia

• bacteria

• fungi

• mold

Tags

NGSS.MS-LS2-3

Which of the following is an example of an anthropogenic effect on the nitrogen cycle?

• Lightning converts atmospheric nitrogen into usable nitrogen.

• Bacteria in nodules on the roots of legumes convert ammonia into nitrates.

• Rain washes excess fertilizer from a farm into a nearby stream.

• The nitrogen in decomposing organisms converts back to ammonia.

Tags

NGSS.MS-ESS3-4

What is the purpose of the nitrogen cycle?

• create nitrogen from nothing

• remove nitrogen gas from the atmosphere

• store nitrogen in the ground so that it creates alternative fuel sources

• convert nitrogen from the atmosphere into a form that is usable by organisms