Which nitrogen cycle process is occurring when bacteria convert ammonium to nitrite and then into nitrate?

• nitrogen fixation

• nitrification

• denitrification

• ammonification

• assimilation

Which of these nitrogen cycle processes converts atmospheric nitrogen to a soil form of nitrogen that is usable by plants?

• nitrogen fixation

• nitrification

• denitrification

• ammonification

• assimilation

How much of the atmosphere is composed of nitrogen gas?

• 87%
• 38%
• 78%
• 21%

Organisms that need nitrogen to survive

• only plants
• only animals
• only bacteria
• all living organisms

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

If the atmosphere is 78% N₂, why can't we just get our nitrogen by breathing?

• We have no mechanism to break the triple bond of nitrogen between the atoms.
• Our lungs would be damaged by the N2.
• We need Oxygen for cellular respiration.
• The legumes take it up first.

Plants and animals cannot use nitrogen directly from the air.

• True
• False

Tags

NGSS.MS-LS2-1

After plants and animals contain nitrogen, what puts it back into atmosphere and soil?

• decomposition
• precipitation
• condensation
• bacteria

Tags

NGSS.MS-LS2-3

Nitrification happens in the ______

• Air 
• Soil 
• Ground Water 
• Plants 

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

What is true about nutrients in the ecosystem (such as water, carbon, and nitrogen)?

• They are not affected by humans in the ecosystem.

• They cannot be recovered if they are lost in the ecosystem.

• They cycle through the ecosystem in different forms to support life.

• They are usually only found in one form in the ecosystem to support life.

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3

Which bacteria remove nitrogen from the atmosphere and convert it into nitrogen containing compounds that plants can use?

• nitrogen fixing bacteria

• nitrifying bacteria

• denitrifying bacteria

Tags

NGSS.MS-LS2-3