During assimilation, which substances are absorbed by plant roots?

During assimilation, plants absorb specific nutrients and compounds from the soil that are crucial for their growth and development. Ammonia, nitrogen, and nitrate are key forms of nitrogen that plants can utilize.

Nitrogen is an essential nutrient for plants, as it plays a vital role in the formation of amino acids, proteins, and nucleic acids, which are fundamental for plant structure and function. Ammonia (NH3) and nitrate (NO3-) are directly taken up by plant roots from the soil. Ammonia is often converted in the soil to ammonium ions (NH4+), which can also be absorbed by plants. Nitrate is a more readily available form of nitrogen in many soils, particularly in well-fertilized agricultural systems.

This combination of ammonia and nitrate contributes to a plant's ability to synthesize vital organic molecules necessary for growth. Consequently, the choice indicating ammonia, nitrogen, and nitrate accurately reflects the assimilation process where these key nitrogen compounds are absorbed by plant roots to support their life processes.