Explain why locating the origin of replication on one side of the circular chromosomes and the terminus of replication on the opposite side of the chromosome supported this conclusion.

If DNA is replicated in a unidirectional manner, the origin and terminus would be overlapped, since the process would begin and end at the same points on the circular chromosome. As the origin of replication and the terminus of replication of the chromosomes are located on the opposite sides, this requires two forks that proceed replication at the same rate in both the directions, with forks moving through half of the chromosome.

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.