The researchers studied how different levels of nitrogen affect how rice seedlings process nitrogen. They found that the activity of certain enzymes in the leaves and roots changed depending on the nitrogen level. Enzyme activity increased in leaves with more nitrogen, but dropped in roots at high nitrogen levels. The amount of protein, amino acids, and chlorophyll in the leaves and roots also increased with more nitrogen. Overall, the study showed that nitrogen levels can impact how rice seedlings metabolize nitrogen, with different effects in leaves and roots.