Answer:
The atmosphere is the largest reservoir of the nitrogen as it is composed of 78% of Nitrogen. Although 78%, this is not used by the organisms directly as the nitrogen molecule exists in nature in the form of divalent joined via triple bonds.
These triple bonds require a great amount of energy to be broken and used. Only a few prokaryotic organisms called nitrogen-fixing bacteria have the capability to break these triple bonds as they contain enzymes-nitrogenase complex which converts the atmospheric nitrogen to usable forms like ammonia, nitrates and nitrites. About 92% of the atmospheric nitrogen is fixed through this way rest through thunderstorms and Haber's process.
Thus, nitrogen-fixing bacteria is the answer.
Answer:
C) When common lands are protected, land degradation slowly disappears.
Explanation:
Xylem Phloem are the vascular tissues that transport the food, minerals and water within the plant. Xylem transport the water and minerals while Phloem transport food and nutrients. The movements in Xylem is unidirectional from roots to aerial parts while the movements in Phloem are bidirectional.