What kind of organisms assist plants in obtaining nitrogen? what is the name for this type of symbiosis?

Answer 1

Nitrogen-fixing bacteria perform this function.

Since the relationship benefits the plants and the bacteria, it is mutualism. The plants get the nitrogen. The bacteria get a place to live on the plant roots.

Answer 2

The process of chemically altering unusable, free atmospheric nitrogen into a form usable by organisms is referred to as nitrogen fixation. In nature, there are two main ways of "fixing" nitrogen:

FIRST WAY: Lightning. If you've ever been close to a lightning flash and right afterwards smelled an ammonia-like odor, that was lightning-fixed nitrogen you smelled. Only a relatively small percentage of nitrogen gets fixed in this way, however. Nature's main nitrogen fixers are...

SECOND WAY: Special microorganisms living mostly in soil and water.