Previous year MCQs

General science UPPSC 2019 GS-I
Question

Which of the following is associated with biological nitrogen fixation ?

Answer & Solution

Answer: (Detailed Solution Below)

Option D: Blue-Green Algae

Detailed Solution:

The correct answer is “Blue-Green Algae”.
Blue-Green Algae are associated with biological nitrogen fixation.  

These organisms, also known as cyanobacteria, have the ability to convert atmospheric nitrogen into a usable form, such as ammonia. This process is crucial for plant growth and soil fertility, as nitrogen is an essential nutrient for plants.

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