Organ systems of the human body interact to maintain a balanced internal environment. IDENTIFY *TWO* of the following body systems, and EXPLAIN how they work together to maintain homeostasis.[Digestive, Circulatory, Respiratory, Excretory, Nervous, Endocrine]

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.

meiosis is the first to occur after the nuclei of opposite of opposite mating types fuse

whats the drop down answers ?

explanation: