Nitrogen Cycle

What is the % of Nitrogen in the air?

• 21%

• 87%

• 78%

• 50%

Living organisms need Nitrogen to make which of the following?

• Glucose

• Proteins

• Sunlight

• Ultraviolet Radiation

How can Nitrogen gas (N₂) be fixed into a usable form for plants?

• Through the action of bacteria only

• Through lightning only

• Through the action of bacteria and lightning

How can Nitrogen gas (N₂) be fixed into a usable form for plants?

• Through the action of bacteria only

• Through lightning only

• Through the action of bacteria and lightning

True or False- Bacteria fix nitrogen from the atmosphere into a form that plants can use.

• True

• False

True or False- Animals can get the Nitrogen they need directly from the soil bacteria just like plants do.

• True

• False

What happens when organisms die and decay? 

• Their bodies are lifted up
• Their nitrogen returns to the soil
• they keep their nitrogen
• They stay on earth forever

What converts nitrogen gas into a usable form for plants and animals?

• bacteria

• rain

• fungi

• car exhaust

How do animals get the nitrogen they need?

• From the air they breathe

• From the water they drink

• From the food they eat

• From the sun

Organisms that play a role in the nitrogen cycle

• only plants
• only animals
• only bacteria
• plants, animals, & bacteria