Class 12th Biology 2012 Set1 Delhi Board Paper Solution
Question 15
Why is Rhizobium categorized as a ‘symbiotic bacterium’ ? How does it act as a biofertiliser ?
Answer
Rhizobium, a symbiotic bacteria, which live in the . root nodule of leguminous plants, fixes atmospheric nitrogen into organic forms to be used by plants. It is a biofertilizer as it is a living organism that enriches nutrient content of the plant. Bacterium gets food and shelter from the plant.
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