In a soil ecosystem rich in decaying organic matter, decomposers rapidly generate ammonium ions (). If a selective metabolic inhibitor specifically disables the functioning of the bacterial genus *Nitrobacter*, which immediate chemical change will occur in the soil, and which subsequent process in the nitrogen cycle will be directly deprived of its primary substrate?
- Nitrite ions () will accumulate in the soil, and denitrification converting nitrate () to nitrogen gas () will be deprived of its substrate.Answer
- BAmmonium ions () will accumulate in the soil, and the conversion of nitrite to nitrate by *Nitrosomonas* will be deprived of its substrate.
- CNitrate ions () will accumulate in the soil, and atmospheric nitrogen fixation by *Azotobacter* will be deprived of its substrate.
- DDinitrogen gas () will accumulate in the soil, and ammonification carried out by saprophytic fungi will be deprived of its substrate.
Answer
Nitrite ions () will accumulate in the soil, and denitrification converting nitrate () to nitrogen gas () will be deprived of its substrate.
In the nitrification process, *Nitrosomonas* first oxidizes ammonium () to nitrite (). *Nitrobacter* then oxidizes nitrite () to nitrate (). If *Nitrobacter* is selectively inhibited, nitrite () accumulates because it is continually produced but not consumed. Furthermore, denitrifying bacteria depend on nitrate () to generate nitrogen gas (); thus, the absence of nitrate production directly deprives denitrification of its substrate.
Step-by-Step Solution
Key Concept
Nitrification and Denitrification Pathway Interdependence
Estimated Time:2m 0s