Lighting and some bacteria "fix" free nitrogen gas. Which of the following best describes nitrogen fixation

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Explanation:

Nitrogen fixation is a process during which free atmospheric molecular nitrogen is converted into biologically usable forms such as ammonia, nitrates, and nitrites. The fixation of nitrogen is naturally carried out in two ways:

1. Direct conversion of molecular nitrogen to nitrates and or ammonia during lightning. The converted compound is washed into the soil by rain and becomes available to plants for uptake.

2. Biological nitrogen fixation: This involves the conversion of nitrogen to ammonium compounds by nitrogen-fixing bacteria that are usually associated with the root nodules of leguminous plants. The compounds thus formed become available for plant use.

Nitrogen can also be artificially fixed into nitrogen-rich fertilizers through various industrial processes. The fertilizers are applied to plants and get into the nitrogen cycle from thereon.