Question

model 2: the nitrogen cycle

1. in what ways is n₂ gas removed from the atmosphere?
2. name 3 types of bacteria involved in the nitrogen cycle

Explanation:

For question 8, from the nitrogen - cycle diagram, nitrogen gas ($N_2$) is removed from the atmosphere through nitrogen - fixing bacteria (found in nodules of legumes and in the soil) and through lightning which causes nitrogen fixation. For question 9, the diagram shows nitrifying bacteria, denitrifying bacteria, and nitrogen - fixing bacteria as types of bacteria involved in the nitrogen cycle.

Answer:

1. Through nitrogen - fixing bacteria and lightning.
2. Nitrifying bacteria, denitrifying bacteria, nitrogen - fixing bacteria.