NTA Abhyas 2020
- Exam
- NTA Abhyas
- Year
- 2020
- Subject
- Botany
- Chapter
- Mineral Nutrition
NTA Abhyas 2020 · Botany · Mineral Nutrition
Select the correctly matched ones from the following. I....
Select the correctly matched ones from the following.
I. Nitrosomonas - Nitrite to nitrate
II. Thiobacillus - Denitrification
III. Nostoc - Free-living nitrogen-fixer
IV. Azotobacter - Anaerobic nitrogen-fixer
I. Nitrosomonas - Nitrite to nitrate
II. Thiobacillus - Denitrification
III. Nostoc - Free-living nitrogen-fixer
IV. Azotobacter - Anaerobic nitrogen-fixer
&
Options
- AI and II
- BIII and IV
- CII and III
- DII and IV
Correct answer
C. II and III
Step-by-step solution
Nitrate present in the soil is reduced to nitrogen by the process of denitrification. Denitrification is carried by bacteria Pseudomonas and Thiobacillus. A number of cyanobacteria such as Anabaena and Nostoc are free-living nitrogen-fixers. Azotobacter and Beijernickia are free-living nitrogen-fixing aerobic microbes. Nitrosomonas and/or Nitrosococcus oxidise NH_{3}& to nitrite. The nitrite is further oxidised to nitrate with the help of Nitrobacter and Nitrocystis.