EASY
DIFFICULT
HARD
100

What form of nitrogen is abundant in the atmosphere?

Nitrogen gas (N₂).

100

Which organisms mainly carry out decomposition and ammonification

Bacteria and fungi.

100

Why can't most plants directly use atmospheric nitrogen?

N₂ is chemically unavailable.

200

How much of the atmosphere is nitrogen gas?

About 78%.

200

What is the nitrogen cycle?

Movement of nitrogen through ecosystems.

200

How do you think the nitrogen cycle useful in wastewater treatment

Removes excess nitrogen.

300

What is the nitrogen cycle?

Movement of nitrogen through ecosystems.

300

What environmental problem can result from excess nitrogen in water?

Eutrophication

300

How do you think understanding the nitrogen cycle help farmers?

Improves fertilizer management.