AP BIOLOGY

Detailed explanation-1: -Nitrogen-fixing bacteria play a crucial role in fixing atmospheric nitrogen into nitrogen compounds that can be used by plants. The plants absorb the usable nitrogen compounds from the soil through their roots. Then, these nitrogen compounds are used for the production of proteins and other compounds in the plant cell.

Detailed explanation-2: -Bacteria play a key role in the nitrogen cycle. Some species of nitrogen-fixing bacteria are free-living in soil or water, while others are beneficial symbionts that live inside of plants.

Detailed explanation-3: -The role of nitrogen-fixing bacteria is to supply plants with the vital nutrient that they cannot obtain from the air themselves. Nitrogen-fixing microorganisms do what crops can’t – get assimilative N for them. Bacteria take it from the air as a gas and release it to the soil, primarily as ammonia.

Detailed explanation-4: -Nitrogen-fixing bacteria fix atmospheric nitrogen to ammonia and then convert it into nitrites and nitrates which can then be taken up by plants. This process is called biological nitrogen fixation. Nitrogen-fixing bacteria may be free-living or symbiotic.

Detailed explanation-5: -In the fifth stage of the nitrogen cycle, nitrogen returns to the air as nitrates are converted to atmospheric nitrogen (N2) by bacteria through the process we call denitrification.