What are the conditions necessary for fixation of atmospheric N2

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsLong Answer Type

81. Describe how nodulation occurs ?
133 Views

82. Name at least five different deficiency symptoms in plants. Describe them and correlate them with concerned mineral deficiency.
402 Views

 Multiple Choice QuestionsShort Answer Type

83. What do you understand by heterotrophic mode of nutrition ? 
239 Views

 Multiple Choice QuestionsLong Answer Type

84.

Why is that in certain plants deficiency symptoms appear first in younger parts of the plant while in others they do so in mature organs?

240 Views

Advertisement
Advertisement

85. What are the conditions necessary for fixation of atmospheric N2 by Rhizobium ? What is their role in N2 fixation.


Conditions for N2 fixation : There are following conditions necessary for N2 fixation :

(1) A strong reducing agent like NADPH : It supplies hydrogen to N2.

(2) ATP as source of energy : It provides energy. For fixation of NH3 molecules, 8 ATP molecules are needed.

(3) The enzyme system : Nitrogenase is necessary for N2 fixation.

(4) Compound for trapping ammonia : Ammonia is very toxic and needs to be trapped in the form of amino acids.

(5) Leghaemoglobin : It is O2 scavenger and maintains anaerobic environment otherwise in the presence of O2 the enzyme nitrogenase is toxicated.

234 Views

Advertisement

 Multiple Choice QuestionsShort Answer Type

86. Describe the passive mineral absorption.
361 Views

 Multiple Choice QuestionsLong Answer Type

87. All elements that are present in plant need not be essential to its survival. Comment.
238 Views

 Multiple Choice QuestionsShort Answer Type

88. Why is purification of water and nutrient salts so important in studies involving mineral nutrition using hydroponics?
251 Views

Advertisement
89. How are the minerals absorbed by the plants?
184 Views

90.

Which of the following statements are true? If false, correct them.

1. Boron deficiency leads to stout axis.

2. Every mineral element that is present in the cell is needed by cell.

3. Nitrogen as a nutrient is highly immobile in the plants.

4. It is very easy to establish the essentiality of micronutrients, because they are required in traces.

237 Views

Advertisement