What if researchers followed a similar method used in this activity to calculate the correlation coefficients for the gene expression patterns of every patient with osteosarcoma and they found that all patients fell into two categories of gene expression patterns? What would this tell you about the single disease we call osteosarcoma? How might this information affect osteosarcoma cancer patient diagnosis and treatment in the future?

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.