Question

How does Nostoc fix nitrogen?

Answer 1

Nitrogen fixation by Nostoc:

1. Nostoc is one of the world's oldest cyanobacterium, having lived on the planet for about 3.5 billion years, according to fossil records.
2. Nostoc has a protective layer that allows it to survive in harsh situations such as drought and flooding, as well as intense heat and cold. Some Nostoc species can survive freezing and thawing cycles, allowing them to dwell in both the Arctic and the Antarctic.
3. Nostoc performs another distinctive activity that is commonly linked with leguminous plants, in addition to photosynthesis.
4. Nostoc absorbs nitrogen from the air and converts it into a form that plants and animals can use.
5. Nitrogen is used by all living species to produce amino acids, proteins, and other essential building blocks. While the earth's atmosphere contains over 80% nitrogen gas, the gas form (N₂) is ineffective for most living creatures.
6. To be used, nitrogen must first be converted to an ammonia form (NH₃). Whereas legumes work with rhizobia bacteria in the soil to fix nitrogen, Nostoc colonies create heterocysts, which are specialized nitrogen-fixing cells. Larger cyanobacteria cells that do not photosynthesize are known as heterocysts.
7. In comparison to legumes, which contribute twenty-five to several hundred pounds of nitrogen per year, Nostoc gives only 5 pounds of nitrogen per year to the environment.
8. Even while this modest amount of nitrogen is insufficient for most cultivated crops, it is plenty for a natural ecosystem. Rice is an interesting crop that may benefit from Nostoc's nitrogen fixation. Nostoc is commonly prevalent in rice paddy cultivation due to its capacity to live in excessively damp environments.