Question

During $N_2$ fixation, reduction of one molecule of nitrogen into $2$ molecules of $NH_3$ consumes__ molecules of $ATP$.

• A. $4$
• B. $16$
• C. $56$
• D. $38$

Answer 1

Answer: (B)

$16$

Answer 2

The chemical equation of nitrogen fixation can be summarised as : ${N2 +8e- +8H+ + 16 ATP ->[\text{dinitrogenase}] 2NH3 + H2 +16 ADP +16 Pi}$ $ATPs$ are provided by photosynthesis and respiration.