Nitrogen Cycle

Question 1

Nitrification

Answer 1

This is the process by which ammonium gets changed into nitrates by bacteria. Nitrates are what the plants can then absorb.

Question 2

Fixation

Answer 2

Fixation is the first step in the process of making nitrogen usable by plants. Here bacteria change nitrogen into ammonium.

Question 3

Assimilation

Answer 3

This is how plants get nitrogen. They absorb nitrates from the soil into their roots. Then the nitrogen gets used in amino acids, nucleic acids, and chlorophyll.

Question 4

Denitrification

Answer 4

Extra nitrogen in the soil gets put back out into the air. There are special bacteria that perform this task as well.

Question 5

Ammonification

Answer 5

This is part of the decaying process. When a plant or animal dies, decomposers like fungi and bacteria turn the nitrogen back into ammonium so it can reenter the nitrogen cycle.