Living Environment Regents Practice Test

What is the primary role of nitrogen fertilizers in global agriculture?

1. To protect the environment

2. To decrease yield costs

3. To produce plant-reactive compounds

4. To eliminate soil bacteria

The correct answer is: To produce plant-reactive compounds

The primary role of nitrogen fertilizers in global agriculture is to enhance plant growth and productivity by providing essential nutrients, particularly nitrogen, which is a key component of amino acids, proteins, and nucleic acids. In plants, nitrogen is critical for the synthesis of chlorophyll and relates directly to photosynthesis, which is vital for plant vigor and yield. When nitrogen is applied as a fertilizer, it becomes available to plants in the form of nitrate or ammonium compounds. These compounds are directly absorbed by plant roots and integrated into biochemical processes that support growth and reproductive capability, leading to increased crop yields. While nitrogen fertilizers can have implications for environmental concerns, such as runoff leading to water quality issues, their primary function remains tied to improving agricultural productivity through the provision of nitrogen that stimulates growth. Other options do not capture this essential role; for instance, the idea that nitrogen fertilizers decrease yield costs or eliminate soil bacteria doesn't reflect their primary purpose in supporting plant health and growth.