Rhizobia are soil bacteria that have the ability to do just that - convert nitrogen into ammonia. They multiply and form nodules attached to the plant roots of leguminous plants such as peas and beans. There are multiple species of rhizobia and not all can form nodules in all leguminous plants.
Karyotyping can give information on a persons sex and chromosomal disorders. It cannot give information on a persons trait's and how severe a disorder is.
