- 1(current)
Q. No.Which one of the following is not a nitrogen-fixing organism?
| 1. | Anabaena | 2. | Nostoc |
| 3. | Azotobacter | 4. | Pseudomonas |
Subtopic: Â Microbes as Biofertilizer |
 90%
Level 1: 80%+
Hints
Match each item in Column I [Diazotroph] with the feature in Column II and select the correct answer from the codes given below:
|
|
Column I |
|
Column II |
|
A. |
Cyanobacteria |
a. |
Actinorhizal symbiont |
|
B. |
Frankia |
b. |
Do not form nodules |
|
C. |
Rhizobium |
c. |
Free-living nitrogen fixer |
|
D. |
Azotobacter |
d. |
Legume symbiont |
Codes
| A | B | C | D | |
| 1. | a | b | c | d |
| 2. | b | a | c | d |
| 3. | a | b | d | c |
| 4. | b | a | d | c |
Subtopic: Â Microbes as Biofertilizer |
 59%
Level 3: 35%-60%
Hints
Identify the correct statements:
1. Only Statement I and Statement II.
2. Only Statement III.
3. Only Statement I.
4. Statement I, Statement II and Statement III.
| Statement I: | Rhizobium forms symbiotic associations and forms nodules on the roots of non-leguminous plants. |
| Statement II: | Azotobacter and Azospirillum can fix atmospheric nitrogen only as symbionts. |
| Statement III: | Anabaena, Nostoc and Oscillatoria are autotrophic microbes capable of fixing atmospheric nitrogen. |
2. Only Statement III.
3. Only Statement I.
4. Statement I, Statement II and Statement III.
Subtopic: Â Microbes as Biofertilizer |
 74%
Level 2: 60%+
Hints
- 1(current)
Q. No.
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