Nitrogen Cycle Review Lesson

Multiple Choice

About what percent of the atmosphere is nitrogen gas (N2)?

• 28%

• 10%

• 78%

• 50%

Multiple Select

What do all living things need nitrogen for (hint: two answers)

• Build amino acids to make proteins

• Create fats

• Create DNA and RNA

• Create carbohydrates

Multiple Choice

Most organisms can take in nitrogen in the form of nitrogen gas (N2) from the atmosphere and then use it to build proteins and nucleic acids.

• True

• False

Multiple Choice

A biogeochemical cycle which models how the element nitrogen moves between the atmosphere, geosphere, biosphere and hydrosphere.

• Carbon Cycle

• Nitrogen Cycle

• Sulfur Cycle

• Phosphorus Cycle

Multiple Choice

Primary environmental factor which allows for the chemical transformation of nitrogen from one compound to another (moves nitrogen through many parts of the nitrogen cycle).

• Animals

• Soil

• Bacteria

• Plants

Multiple Select

Which of the following are forms of nitrogen which appear in the nitrogen cycle?

• Ammonia (NH3) / Ammonium (NH4)

• Nitrogen Gas (NH2)

• Nitrite (NO2)

• Nitrate (NO3)

Multiple Select

What are TWO ways which nitrogen is "fixed" from the atmosphere?

• Lightening changes nitrogen gas (N2) to nitrate (NO3).

• Bacteria change ammonia (NH3) to nitrate (NO3)

• Bacteria change nitrate (NO3) to nitrogen gas

• Bacteria change nitrogen gas (N2) to ammonia (NH3)

Multiple Choice

Category of plan that has a symbiotic relationship which nitrogen fixing bacteria. The bacteria is located in their roots. The bacteria fixes nitrogen gas from the atmosphere turning it into ammonia (NH3). The plant can then take in this ammonia / ammonium to use the nitrogen to build proteins and nucleic acids.

• Legumes

• Coniferous Trees

• Deciduous Trees

Multiple Choice

Most species of plants can use ammonia / ammonium as a source of nitrogen.

• True

• False

Multiple Choice

Once nitrogen has been fixed and is in the form of ammonia / ammonium, what process comes next in the cycle?

• Ammonification

• Nitirification

• Denitrification

• Fixation

Multiple Select

What two nitrogen cycle processes could supply nitrogen compounds to bacteria which do nitrification. (Hint: 2 answers)

• Fixation

• Ammonification

• Denitrification

• Assimilation

Multiple Choice

The process where ammonia / ammonium gets changed into nitrite (NO2) and then nitrate (NO3)...

• Fixation

• Ammonification

• Nitrification

• Denitrification

Multiple Choice

What organism is most needed for nitrification (ammonia / ammonium --> nitrate) to occur in the soil?

• Plants

• Bacteria

• Animals

• Decomposers

Multiple Select

What nitrogen cycle processes could occur directly after nitrification (hint: 2 answers)

• Fixation

• Ammonification

• Assimilation

• Denitrification

Multiple Choice

The process by which most plant species take up nitrogen in the form of nitrate (NO3) from the environment.

• Nitrification

• Denitrification

• Ammonification

• Fixation

• Assimilation

Multiple Choice

What structure do plants use to absorb nitrates?

• Roots

• Stem

• Leaves

• Flowers

Multiple Select

From which processes in the nitrogen cycle could nitrates come from? (Hint: 2 answers)

• Lightening Fixation

• Denitrification

• Ammonification

• Nitrification

Multiple Choice

Once plants absorb and assimilate (build their DNA and Proteins) nitrogen, how do animals get that nitrogen?

• Consumption of plants and other animals

• Photosynthesis

• Root uptake

• Ammonification

Multiple Choice

What kind of organism is closely associated with ammonifcation?

• Consumers

• Producers

• Decomposers

Multiple Choice

What process is driven by decomposers that transfers nitrogen inside plants and animals back into ammonia / ammonium in the soil?

• Assimilation

• Nitrification

• Ammonification

• Denitrfication

• Fixation

Multiple Select

What are two inputs to the processes of ammonification?

• Dead organisms

• Rocks

• Waste from organisms

• Air

Multiple Choice

Once bacteria or fungi have broken down organic matter (dead organisms / waste) and create ammonia / ammonium, what nitrogen cycle process could occur next?

• Denitrification

• Nitrification

• Lightening Fixation

• Bacterial Fixation

Multiple Choice

Denitrification is a chemical process which transforms nitrates (NO3) in the soil to nitrogen gas (N2) which goes back into the atmosphere. What organism primarily drives this process?

• Plants

• Animals

• Bacteria

• All decomposers

Multiple Choice

The process by which nitrogen in the soil, mostly in the form of nitrates (NO3) is converted into nitrogen gas (N2) which is transferred back to the atmosphere.

• Nitrification

• Fixation

• Denitrification

• Ammonification

Multiple Choice

Which nitrogen cycle process is likely to come before denitrification

• Ammonification

• Fixation

• Nitrification

• Assimilation

Multiple Choice

Which nitrogen cycle process is likely to come after denitrification

• Fixation

• Ammonification

• Nitrification

• Assimilation