Nitrogen Cycle Quiz

What is nitrogen cycle?

• A biochemical process through which nitrogen is converted into many forms.

• A process that only occurs in plants.

• A method of nitrogen storage in the atmosphere.

• A chemical reaction that does not involve living organisms.

What makes it support life?

• Nitrogen is essential for building important molecules.

• Nitrogen is harmful to living organisms.

• Nitrogen has no role in supporting life.

• Nitrogen is only needed by plants.

What are the essential molecules that need nitrogen?

• Proteins, DNA & RNA, Chlorophyll

• Water, Carbohydrates, Lipids

• Vitamins, Minerals, Sugars

• Fats, Oils, Starches

What is the initial step of the nitrogen cycle?

• Fixation

• Nitrification

• Assimilation

• Ammonification

What happens during nitrification?

• Ammonia is converted into nitrate.

• Nitrogen is fixed into ammonia.

• Organic matter is decomposed.

• Plants absorb nitrogen.

What is assimilation in the nitrogen cycle?

• Plants take in nitrogen compounds from the soil.

• Nitrogen is released back into the atmosphere.

• Bacteria convert ammonia into nitrate.

• Decomposers break down organic matter.

What occurs during ammonification?

• Nitrogen is released back into the soil.

• Plants absorb nitrogen.

• Nitrate is converted into ammonia.

• Nitrogen is fixed into organic matter.

Which process in the nitrogen cycle converts atmospheric nitrogen (N₂) into a form usable by plants?

• Denitrification

• Nitrification

• Nitrogen fixation

• Ammonification

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

• They convert ammonia into nitrogen gas.

• They convert nitrates into nitrogen gas.

• They convert ammonia into nitrites and nitrates.

• They fix nitrogen from the atmosphere.

Which step of the nitrogen cycle returns nitrogen to the atmosphere?

• Nitrogen fixation

• Nitrification

• Assimilation

• Denitrification