343780
Which one of the following statements is correct?
1 Both Azotobactor and Rhizobium fix atmospheric nitrogen in root nodules of plants
2 Cyanobacteria such as Anabaena and Nostoc are important mobilizers of phosphates and for plant nutrition in soil
3 Biofertilisers are chemical fertilisers that enrich the nutrient quality of the soil.
4 Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies
Explanation:
Root nodules are formed when nitrogenfixing bacteria called Rhizobia enter the cells of a host leguminous plant. Azotobacter is a genus of free-living diazotrophic bacteria whose resting stage is a cyst. It is primarily found in neutral to alkaline soils, in aquatic environments, and on some plants. It helps in atmospheric nitrogen fixation by conversion to ammonia. Cyanobacteria, Anabaena and Nostoc are mobilizers of nitrates and plant nutrition in soil. Organic fertilizers can be used to grow maize. Unlike chemical fertilizers, organic fertilizers reduce acidity in the soil and do not cause leaching. They do not kill beneficial micro-organisms in the soil. The prime contaminants are nitrates and phosphates, which act as plant nutrients and causes the excessive growth of algae which reduces the dissolved oxygen from water, vital to other aquatic life.
BIOXII10: MICROBES IN HUMAN WELFARE
343781
Mycorrhiza does not help the host plant in:
1 Enhancing its phosphorus uptake capacity
2 Increasing its tolerance to drought
3 Enhancing its resistance to root pathogens
4 Increasing its resistance to insects.
Explanation:
Mycorrhiza does not help the host plant in: Increasing its resistance to insects.
NCERT Exemplar
BIOXII10: MICROBES IN HUMAN WELFARE
343782
Which one of the following are not free living \(\mathrm{N}_{2}\) fixing cyanobacteria
1 Anabaena
2 Nostoc
3 Aulosira
4 Rhizobium
Explanation:
Except Rhizobium all are free living nitrogen fixing cyanobacteria.
AIPMT - 2011
BIOXII10: MICROBES IN HUMAN WELFARE
343784
A nitrogen fixing microbe associated with Azolla in rice fields is
1 Frankia
2 Rhizobium
3 Spriulina
4 Anabaena
Explanation:
Anabaena azollae, a cyanobacterium that lives in symbiotic association with the freefloating water fern Azolla. Anabaena azollae can grow Photo-autotrophically and fixes atmospheric nitrogen.
BIOXII10: MICROBES IN HUMAN WELFARE
343785
Farmers have reported over \(50 \%\) higher yields of rice by using the biofertilizer :
1 Mycorrhiza
2 Azolla pinnata
3 Cyanobacteria
4 Legume- Rhizobium symbiosis
Explanation:
Anabaena azollae , a cyanobacterium living in the cavities of fern Azolla, fixes atmospheric nitrogen and releases it into the leaf cavity of the fern. Farmers have reported over 50% higher yields by using Azolla pinnata .
343780
Which one of the following statements is correct?
1 Both Azotobactor and Rhizobium fix atmospheric nitrogen in root nodules of plants
2 Cyanobacteria such as Anabaena and Nostoc are important mobilizers of phosphates and for plant nutrition in soil
3 Biofertilisers are chemical fertilisers that enrich the nutrient quality of the soil.
4 Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies
Explanation:
Root nodules are formed when nitrogenfixing bacteria called Rhizobia enter the cells of a host leguminous plant. Azotobacter is a genus of free-living diazotrophic bacteria whose resting stage is a cyst. It is primarily found in neutral to alkaline soils, in aquatic environments, and on some plants. It helps in atmospheric nitrogen fixation by conversion to ammonia. Cyanobacteria, Anabaena and Nostoc are mobilizers of nitrates and plant nutrition in soil. Organic fertilizers can be used to grow maize. Unlike chemical fertilizers, organic fertilizers reduce acidity in the soil and do not cause leaching. They do not kill beneficial micro-organisms in the soil. The prime contaminants are nitrates and phosphates, which act as plant nutrients and causes the excessive growth of algae which reduces the dissolved oxygen from water, vital to other aquatic life.
BIOXII10: MICROBES IN HUMAN WELFARE
343781
Mycorrhiza does not help the host plant in:
1 Enhancing its phosphorus uptake capacity
2 Increasing its tolerance to drought
3 Enhancing its resistance to root pathogens
4 Increasing its resistance to insects.
Explanation:
Mycorrhiza does not help the host plant in: Increasing its resistance to insects.
NCERT Exemplar
BIOXII10: MICROBES IN HUMAN WELFARE
343782
Which one of the following are not free living \(\mathrm{N}_{2}\) fixing cyanobacteria
1 Anabaena
2 Nostoc
3 Aulosira
4 Rhizobium
Explanation:
Except Rhizobium all are free living nitrogen fixing cyanobacteria.
AIPMT - 2011
BIOXII10: MICROBES IN HUMAN WELFARE
343784
A nitrogen fixing microbe associated with Azolla in rice fields is
1 Frankia
2 Rhizobium
3 Spriulina
4 Anabaena
Explanation:
Anabaena azollae, a cyanobacterium that lives in symbiotic association with the freefloating water fern Azolla. Anabaena azollae can grow Photo-autotrophically and fixes atmospheric nitrogen.
BIOXII10: MICROBES IN HUMAN WELFARE
343785
Farmers have reported over \(50 \%\) higher yields of rice by using the biofertilizer :
1 Mycorrhiza
2 Azolla pinnata
3 Cyanobacteria
4 Legume- Rhizobium symbiosis
Explanation:
Anabaena azollae , a cyanobacterium living in the cavities of fern Azolla, fixes atmospheric nitrogen and releases it into the leaf cavity of the fern. Farmers have reported over 50% higher yields by using Azolla pinnata .
343780
Which one of the following statements is correct?
1 Both Azotobactor and Rhizobium fix atmospheric nitrogen in root nodules of plants
2 Cyanobacteria such as Anabaena and Nostoc are important mobilizers of phosphates and for plant nutrition in soil
3 Biofertilisers are chemical fertilisers that enrich the nutrient quality of the soil.
4 Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies
Explanation:
Root nodules are formed when nitrogenfixing bacteria called Rhizobia enter the cells of a host leguminous plant. Azotobacter is a genus of free-living diazotrophic bacteria whose resting stage is a cyst. It is primarily found in neutral to alkaline soils, in aquatic environments, and on some plants. It helps in atmospheric nitrogen fixation by conversion to ammonia. Cyanobacteria, Anabaena and Nostoc are mobilizers of nitrates and plant nutrition in soil. Organic fertilizers can be used to grow maize. Unlike chemical fertilizers, organic fertilizers reduce acidity in the soil and do not cause leaching. They do not kill beneficial micro-organisms in the soil. The prime contaminants are nitrates and phosphates, which act as plant nutrients and causes the excessive growth of algae which reduces the dissolved oxygen from water, vital to other aquatic life.
BIOXII10: MICROBES IN HUMAN WELFARE
343781
Mycorrhiza does not help the host plant in:
1 Enhancing its phosphorus uptake capacity
2 Increasing its tolerance to drought
3 Enhancing its resistance to root pathogens
4 Increasing its resistance to insects.
Explanation:
Mycorrhiza does not help the host plant in: Increasing its resistance to insects.
NCERT Exemplar
BIOXII10: MICROBES IN HUMAN WELFARE
343782
Which one of the following are not free living \(\mathrm{N}_{2}\) fixing cyanobacteria
1 Anabaena
2 Nostoc
3 Aulosira
4 Rhizobium
Explanation:
Except Rhizobium all are free living nitrogen fixing cyanobacteria.
AIPMT - 2011
BIOXII10: MICROBES IN HUMAN WELFARE
343784
A nitrogen fixing microbe associated with Azolla in rice fields is
1 Frankia
2 Rhizobium
3 Spriulina
4 Anabaena
Explanation:
Anabaena azollae, a cyanobacterium that lives in symbiotic association with the freefloating water fern Azolla. Anabaena azollae can grow Photo-autotrophically and fixes atmospheric nitrogen.
BIOXII10: MICROBES IN HUMAN WELFARE
343785
Farmers have reported over \(50 \%\) higher yields of rice by using the biofertilizer :
1 Mycorrhiza
2 Azolla pinnata
3 Cyanobacteria
4 Legume- Rhizobium symbiosis
Explanation:
Anabaena azollae , a cyanobacterium living in the cavities of fern Azolla, fixes atmospheric nitrogen and releases it into the leaf cavity of the fern. Farmers have reported over 50% higher yields by using Azolla pinnata .
343780
Which one of the following statements is correct?
1 Both Azotobactor and Rhizobium fix atmospheric nitrogen in root nodules of plants
2 Cyanobacteria such as Anabaena and Nostoc are important mobilizers of phosphates and for plant nutrition in soil
3 Biofertilisers are chemical fertilisers that enrich the nutrient quality of the soil.
4 Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies
Explanation:
Root nodules are formed when nitrogenfixing bacteria called Rhizobia enter the cells of a host leguminous plant. Azotobacter is a genus of free-living diazotrophic bacteria whose resting stage is a cyst. It is primarily found in neutral to alkaline soils, in aquatic environments, and on some plants. It helps in atmospheric nitrogen fixation by conversion to ammonia. Cyanobacteria, Anabaena and Nostoc are mobilizers of nitrates and plant nutrition in soil. Organic fertilizers can be used to grow maize. Unlike chemical fertilizers, organic fertilizers reduce acidity in the soil and do not cause leaching. They do not kill beneficial micro-organisms in the soil. The prime contaminants are nitrates and phosphates, which act as plant nutrients and causes the excessive growth of algae which reduces the dissolved oxygen from water, vital to other aquatic life.
BIOXII10: MICROBES IN HUMAN WELFARE
343781
Mycorrhiza does not help the host plant in:
1 Enhancing its phosphorus uptake capacity
2 Increasing its tolerance to drought
3 Enhancing its resistance to root pathogens
4 Increasing its resistance to insects.
Explanation:
Mycorrhiza does not help the host plant in: Increasing its resistance to insects.
NCERT Exemplar
BIOXII10: MICROBES IN HUMAN WELFARE
343782
Which one of the following are not free living \(\mathrm{N}_{2}\) fixing cyanobacteria
1 Anabaena
2 Nostoc
3 Aulosira
4 Rhizobium
Explanation:
Except Rhizobium all are free living nitrogen fixing cyanobacteria.
AIPMT - 2011
BIOXII10: MICROBES IN HUMAN WELFARE
343784
A nitrogen fixing microbe associated with Azolla in rice fields is
1 Frankia
2 Rhizobium
3 Spriulina
4 Anabaena
Explanation:
Anabaena azollae, a cyanobacterium that lives in symbiotic association with the freefloating water fern Azolla. Anabaena azollae can grow Photo-autotrophically and fixes atmospheric nitrogen.
BIOXII10: MICROBES IN HUMAN WELFARE
343785
Farmers have reported over \(50 \%\) higher yields of rice by using the biofertilizer :
1 Mycorrhiza
2 Azolla pinnata
3 Cyanobacteria
4 Legume- Rhizobium symbiosis
Explanation:
Anabaena azollae , a cyanobacterium living in the cavities of fern Azolla, fixes atmospheric nitrogen and releases it into the leaf cavity of the fern. Farmers have reported over 50% higher yields by using Azolla pinnata .
343780
Which one of the following statements is correct?
1 Both Azotobactor and Rhizobium fix atmospheric nitrogen in root nodules of plants
2 Cyanobacteria such as Anabaena and Nostoc are important mobilizers of phosphates and for plant nutrition in soil
3 Biofertilisers are chemical fertilisers that enrich the nutrient quality of the soil.
4 Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies
Explanation:
Root nodules are formed when nitrogenfixing bacteria called Rhizobia enter the cells of a host leguminous plant. Azotobacter is a genus of free-living diazotrophic bacteria whose resting stage is a cyst. It is primarily found in neutral to alkaline soils, in aquatic environments, and on some plants. It helps in atmospheric nitrogen fixation by conversion to ammonia. Cyanobacteria, Anabaena and Nostoc are mobilizers of nitrates and plant nutrition in soil. Organic fertilizers can be used to grow maize. Unlike chemical fertilizers, organic fertilizers reduce acidity in the soil and do not cause leaching. They do not kill beneficial micro-organisms in the soil. The prime contaminants are nitrates and phosphates, which act as plant nutrients and causes the excessive growth of algae which reduces the dissolved oxygen from water, vital to other aquatic life.
BIOXII10: MICROBES IN HUMAN WELFARE
343781
Mycorrhiza does not help the host plant in:
1 Enhancing its phosphorus uptake capacity
2 Increasing its tolerance to drought
3 Enhancing its resistance to root pathogens
4 Increasing its resistance to insects.
Explanation:
Mycorrhiza does not help the host plant in: Increasing its resistance to insects.
NCERT Exemplar
BIOXII10: MICROBES IN HUMAN WELFARE
343782
Which one of the following are not free living \(\mathrm{N}_{2}\) fixing cyanobacteria
1 Anabaena
2 Nostoc
3 Aulosira
4 Rhizobium
Explanation:
Except Rhizobium all are free living nitrogen fixing cyanobacteria.
AIPMT - 2011
BIOXII10: MICROBES IN HUMAN WELFARE
343784
A nitrogen fixing microbe associated with Azolla in rice fields is
1 Frankia
2 Rhizobium
3 Spriulina
4 Anabaena
Explanation:
Anabaena azollae, a cyanobacterium that lives in symbiotic association with the freefloating water fern Azolla. Anabaena azollae can grow Photo-autotrophically and fixes atmospheric nitrogen.
BIOXII10: MICROBES IN HUMAN WELFARE
343785
Farmers have reported over \(50 \%\) higher yields of rice by using the biofertilizer :
1 Mycorrhiza
2 Azolla pinnata
3 Cyanobacteria
4 Legume- Rhizobium symbiosis
Explanation:
Anabaena azollae , a cyanobacterium living in the cavities of fern Azolla, fixes atmospheric nitrogen and releases it into the leaf cavity of the fern. Farmers have reported over 50% higher yields by using Azolla pinnata .
