Question

Why living beings cannot use atmospheric nitrogen directly?

Answer 1

Dear student,

Plants cannot use the atmospheric nitrogen because it is present in the gaseous form.
Plants can take only the inorganic form of nitrogen(nitrate, nitrite, ammonia) present in the soil. The conversion of atmospheric nitrogen into the inorganic compound is facilitated by some nitrogen-fixing bacteria, called diazotrophs.

Animals cannot take the gaseous atmospheric nitrogen, they can take only the organic form of it, present in amino acids. Animal derives the organic nitrogen from plants as their food.

Regards.