Nitrogen Cycle

What is the largest reservoir that contains about 78% of all atmospheric nitrogen?

• Bacteria

• Atmosphere

• Soil

• Plants

Nitrogen gas is colorless, odorless, and ____________, causing most organisms to use only

compounds made from nitrogen.

• reactive

• unreactive

The process where N2 molecules in the air break apart and combine with other atoms to form ammonia.

• Ammonification

• Assimilation

• Nitrification

• Nitrogen Fixation

• Denitrification

This type of nitrogen fixation occurs when energy from lightning breaks N2 molecules apart and they combine with oxygen forming N2O.

• Atmospheric Fixation

• Biological Fixation

• Industrial Fixation

Industrial fixation is the process of combining N2 with H2 to form ______.

• Ammonia

• Nitrites

• Nitrates

• Proteins

Tags

NGSS.MS-PS1-5

Animals at the top of the food chain eating plants for their proteins is the process______.

• Ammonificaiton

• Assimilation

• Nitrification

• Denitfrication

Tags

NGSS.MS-LS2-3

NGSS.MS-LS1-6

Returning nitrogen to the atmosphere by bacteria living deep in swampy sediments is the process ______.

• Ammonification

• Assimilation

• Denitrification

• Nitrogen Fixation

Ammonification is part of the ______ process.

• decay

• dying

• growing

• living

Tags

NGSS.MS-LS2-3

This form of nitrogen fixation is where most nitrogen “fixing” takes place.

• Atmospheric Fixation

• Biological Fixation

• Industrial Fixation

Nitrogen fixing by bacteria living in root nodules of plants is called a _______ relationship.

• Asexual

• Symbiotic

• Cyclical

• Fraternal