Why is nitrogen essential to the growth of a fungus, but not to the spread of rust?
A fungus is a living organism, while rust is not
What can you infer from the fact that nitrogen gas is useless to animals?
Animal cells can only use nitrogen when its combined with other elements
What conclusion can you draw from the fact that sewage adds compounds to the environment?
Animals get rid of nitrogen compounds in their waste
What describes the path of a nitrogen molecule through the environment?
It moves through the environment repeatedly, but not in the same order
What do nitrification and denitifrication have in common?
Both processes involve oxygen atoms
What is the main difference between denitrification and the other three steps of the nitrogen cycle?
Denitrification changes nitrogen into a gaseous form