Nitrogen Cycle Flashcards

Flashcards covering key concepts about the nitrogen cycle based on lecture notes.

What is nitrification?

The process of breaking down ammonia and making it usable for plants.

What role do nitrifying bacteria play in the nitrogen cycle?

They break down ammonia released during decomposition.

How do consumers obtain nitrogen?

Through consumption of other organisms.

What is a heterotroph?

An organism that must eat other organisms to get their food and energy; also known as a consumer.

Provide examples of how nitrogen enters the environment.

Excretion, decomposition, lightning, and nitrogen-fixing bacteria.

What is denitrification?

The process where bacteria break down nitrogen in the soil and release it into the atmosphere.

How does nitrogen get back to the atmosphere?

Through denitrification, where usable forms of nitrogen are taken from the soil and returned to the atmosphere by bacteria.

What is nitrogen fixation?

The process of converting atmospheric nitrogen into usable forms.

What are two ways nitrogen fixation can occur?

Through lightning strikes and through bacteria.

How does lightning contribute to nitrogen fixation?

Lightning changes the chemistry of nitrogen in the atmosphere to make it usable for plants.

How do nitrogen-fixing bacteria contribute to nitrogen fixation?

They use nitrogen from the atmosphere for energy and in doing so, make nitrogen available for plants.

Describe the symbiotic relationship between legumes and nitrogen-fixing bacteria.

Legume roots form a symbiotic relationship with nitrogen-fixing bacteria, which fix nitrogen from the atmosphere into organic nitrogen and release it into the soil for plants to use.

Why are legumes important in crop rotations?

They produce usable forms of nitrogen for plants in the soil.