Nitrogen Cycle Flashcard

Front

Which gas makes up ____ percent of our atmosphere but can be used by plants only when transformed by bacteria first?

Back

78%

Front

In order for plants to absorb nitrogen, it must be transformed first and is called

Back

nitrogen fixation

Front

Nitrogen enters food chains through ________. Options: plants, factories, car emissions, clouds

Back

plants

Front

What organism converts atmospheric nitrogen into nitrogen compounds that will later be used by plants?

Back

bacteria

Front

In Figure 6.3, which process converts nitrogen gas in the air into? Options: Nitrogen fixation, Decomposition, Respiration, Denitrification

Back

Denitrification

Front

Excessive use of ________ on lawns and gardens can affect the nitrogen and phosphorus cycles in nearby lakes and streams.

Back

fertilizers

Front

Bacteria transform atmospheric nitrogen into nitrates for plants to use during a process called ______________.

Back

nitrogen fixation

Front

The process by which plants absorb ammonia or nitrates is

Back

assimilation

Front

When algae die, oxygen concentration drops, which kills fish and other aquatic organisms. Which process below causes this problem?

• ocean tides
• run off from fertilizer used by farmers
• photosynthesis
• Sunlight

Back

run off from fertilizer used by farmers