How Is Atmospheric Nitrogen Converted to a Usable Form in the Biosphere

question 71

Multiple Choice

How is atmospheric nitrogen converted to a usable form in the biosphere?

• A)Atmospheric nitrogen is directly available to plants and animals through the photosynthetic process and trophic relationships.
• B)It is absorbed into plants via stoma and converted within the plant to a usable form.
• C)Bacteria within root nodules of legumes chemically change the atmospheric nitrogen into nitrates and ammonia.
• D)Atmospheric nitrogen is completely unavailable to plants and animals and,as a result,synthetic fertilizers must be used.
• E)Atmospheric nitrogen combines with atmospheric moisture and a free oxygen molecule to form nitric acids (HNO3),which enters in the biosphere as mildly acidic precipitation.

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Definitions:

Third Variable

A factor that is not directly involved in a research hypothesis but may influence the relationship between the variables being studied.

Correlational Study

A research method that examines the relationship between two or more variables to determine if a correlation exists, without implying causation.

Statistical Significance

Likelihood that a study’s results have occurred only by chance.

Probability

The likelihood or chance that a specific event will occur, often expressed as a ratio or percentage.