Although air is full of nitrogen, it is not available for organisms to readily use. Nitrogen is changed into which substances before being used by living things? A. Oxygen, carbon, water B. Nodules, roots, fertilizer C. Ammonia, nitrates, nitrites D. Phosphorus, nitrates, nodules.
It is essential for all living things. Fixation: In order for organisms to use atmospheric nitrogen (N2), it must be “fixed” or converted into ammonia (NH3).
