During biological nitrogen fixation, inactivation of nitrogenase by oxygen poisoning is prevented by

(1) leghaemoglobin

(2) xanthophyll

(3) carotene

(4) cytochrome

Subtopic:  Nitrogen Fixation |
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NEET 2022 - Target Batch - Aryan Raj Singh
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NEET 2022 - Target Batch - Aryan Raj Singh

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The oxygen evolved during photosynthesis comes from water molecules. Which one of the following pairs of elements involved in this reaction?

1. Manganese and chlorine

2. Manganese and potassium

3. Manganese and molybdenum

4. Magnesium and chlorine

Subtopic:  Mineral Function |
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Minerals known to be required in large amounts for plant growth include

1. Phosphorus, potassium, sulphur, calcium

2. calcium, magnesium, manganese, copper

3. potassium, phosphorus, selenium, boron

4. magnessium, sulphur, iron, zinc

Subtopic:  Classification of Nutrients |
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Deficiency symptoms of nitrogen and potassium are visible first in

1. senescent leaves

2. young leaves

3. roots

4. buds

Subtopic:  Mineral Deficiency & Toxicity |
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NEET 2022 - Target Batch - Aryan Raj Singh
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The most abundant intracellular cation is

1. Na+

2. Ca2+

3. H+

4. K+

Subtopic:  Mineral Function | Classification of Nutrients |
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The first stable product of fixation of atmospheric nitrogen in leguminous plants is

1. NO2-

2. ammonia

3. NO3-

4. glutamate

Subtopic:  Ammonia Assimilation & Nitrogen Export |
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Best defined function of manganese in green plants is

1. photolysis of water

2. Calvin cycle

3. nitrogen fixation

4. water absorption

Subtopic:  Mineral Function |
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Which one of the following is wrong statement?

1. Anabaena and Nostoc are capable of fixing nitrogen in free-living state also

2. Root nodule forming nirogen fixers live as aerobes under free-living conditions

3. Phosphorus is a constituent of cell membranes, certain nucleic acids and all proteins

4. Nitrosomonas and Nitrobacter are chemoautotrophs

Subtopic:  Nitrogen Fixation |
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A nitrogen fixing microbe associated with Azolla in rice fields is

1. Spirulina 

2. Anabaena

3. Frankia

4. Tolypothrix

Subtopic:  Nitrogen Fixation |
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The function of leghaemoglobin in the root nodules of legumes is 

(1) oxygen removal

(2) nodule differentiation

(3) expression of nif gene

(4) inhibition of nitrogenase activity

Subtopic:  Nitrogen Fixation | Nodule formation |
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