A 44 year old man was admitted to the hospital following a 2 week history of low grade fever, malaise, and anorexia. Examination of a Giemsa stained blood film revealed many intraerythrocytic parasites. Further history revealed frequent camping trips near Martha's Vineyard and Nantucket Island, but no travel outside the continental United States. This parasite could easily be confused with:. a. Babesia microti
b. Leishmania donovani
c. Plasmodium ovale
d. Toxoplasma gondii
e. none of these

OPTION C (Plasmodium ovale)

Explanation: The symptoms of the infection is also seen in the listed intraerythrocytic protozoans in the options. However, the travel history of the man establishes that the man wasn't exposed to an intraerythrocytic protozoans which isn't endemic in the United States, and considering the man's trip around vineyard and island which can serve as breeding site of mosquitoes (vector of Plasmodium spp) makes this parasite easily confused with Plasmodium ovale.

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.