Question

In soybean, the product of biological nitrogen fixation is transported from the root nodules to other parts as:
A. Glutamate
B. Ammonia
C. Ureides
D. Nitrates

Answer 1

Hint:
Nitrogen is a crucial element for plant growth and development. It is a major element of chlorophyll needed for photosynthesis, amino acids, and the building blocks of proteins. It is also found in other important biomolecules, such as nucleic acids and ATP. Even though it is the main element required by plants, it is not readily available to use. They can only use a reduced form of nitrogen.

Complete step by step answer:
Nitrogen fixation is the essential biological process and the first stage of the nitrogen cycle. In this process, atmospheric nitrogen is converted into ammonia by certain bacterial species like Azotobacter, Rhizobium, etc., and by other natural phenomena.
The bacteria, such as Rhizobium function by invading the soybean plant root hairs and multiplying to form root nodules. The bacteria have a mutual association with the plant; the plant supplies them with carbohydrates, while the bacteria perform Nitrogen-fixation for the plant. In soybean, the products of fixation are the Ureides, allantoic acid, and allantoin, which are the dominant long-distance transport forms of nitrogen from nodules to the shoot. In soybean, after nitrogen fixation by the bacteroids, ammonia is finally reduced in uninfected cells to allantoic acid and allantoin. Nitrates return to the atmosphere as atmospheric nitrogen (N2) by bacteria through the process of denitrification. Glutamate plays a role in nitrogen assimilation.

Option ‘C’ is correct

Note:
Azospirillum species can form close associations with several members of the grasses and cereal crops, such as wheat, rice, corn, barley, and oats. They can fix an appreciable quantity of nitrogen within the rhizosphere of the host plants.