Of the skulls below, which one shows the most evidence of upright walking?
human evolution
a. skull a
b. skull b
c. skull c
d. skull d

The skull that shows the most evidence of upright walking is actually D :)

the correct answer should be false

{apex}

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.