What are the assumptions for the hardy-weinberg equation? what does it mean when a population is in hardy-weinberg equilibrium?

the Hardy-Weinberg assumptions are:  no mutation, random mating, no gene flow, infinite population size, and no selection.

When a population is in Hardy-Weinberg equilibrium?  Evolution will not occur

***The Hardy-Weinberg equilibrium can be disturbed by a number of forces, including mutations, natural selection, nonrandom mating, genetic drift, and gene flow***

Explanation:

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.