AP BIOLOGY

Detailed explanation-1: -This process is called nitrification. Compounds such as nitrate, nitrite, ammonia and ammonium can be taken up from soils by plants and then used in the formation of plant and animal proteins.

Detailed explanation-2: -Nitrogen assimilation is the process by which inorganic nitrogen compounds are used to form organic nitrogen compounds such as amino acids, amides, etc. Plants and other organisms, which cannot utilise nitrogen molecules directly, depend on the absorption of nitrogen as nitrates or ammonia.

Detailed explanation-3: -Nitrogen-fixing bacteria in the soil and within the root nodules of some plants convert nitrogen gas in the atmosphere to ammonia. Nitrifying bacteria convert ammonia to nitrites or nitrates. Ammonia, nitrites, and nitrates are all fixed nitrogen and can be absorbed by plants.

Detailed explanation-4: -Nitrogen Fixation For nitrogen to be available to make proteins, DNA, and other biologically important compounds, it must first be converted into a different chemical form. The process of converting N2 into biologically available nitrogen is called nitrogen fixation.

Detailed explanation-5: -The process of absorption of nitrogen compounds from the plants is called assimilation. The nitrates present in the soil are converted into free nitrogen by pseudomonas bacteria.