What are flagella?
A. false feet
B. skinny tails
C. hairlike projections
D. temporary extensions

a. suckling by young

b. hypothalamus

c. dopamine

d. trh

e. anterior pituitary

f. mammary glands

g. milk production

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.

bacterium is not correct