Nitrogen cycle

What % of the air is made of nitrogen?

• 21%

• 52%

• 61%

• 78%

Tags

NGSS.MS-PS1-1

True or False. The nitrogen in the atmosphere is in the right form for living things to use.

• True

• False

This can transform nitrogen in the atmosphere into a usable form of nitrogen

• rain

• ice

• lightning

• sun

What is the role of denitrifying bacteria

• change nitrate back into nitrogen gas

• change nitrogen gas into nitrate

• absorb carbon dioxide in the soil

• release oxygen gas into the atmosphere

Tags

NGSS.MS-LS2-3

Round structures on the roots of certain plants

• lichens

• commensals

• cataracts

• nodules

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

• change Nitrogen gas into Nitrate

• Return the nitrogen compounds to the soil

• Turn nitrogen into water

• Turn nitrate into nitrogen gas

Tags

NGSS.MS-LS2-3

We need nitrogen to make

• proteins

• enzymes

• cells

• all of these

Tags

NGSS.MS-LS1-7

Burning fossil fuels releases this into the air

• nitrous oxide

• nitrate

• nitrogen gas (N2)

• methane

How does fertilizer affect the nitrogen cycle

• the bacteria reproduce quicker

• cause nitrous oxide, a greenhouse gas, to enter the atmosphere and trap heat

• create large algae blooms in the water

• cause the nitrogen fixing bacteria in the soil to be less productive

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

NGSS.MS-LS2-4

Where can nitrogen fixing bacteria be found

• Free living in the soil

• under the leaves of flowering plants

• in the atmosphere

• living on the nodules of certain plants