简答题\n When sufficient reducing power is present, ATP can also be produced in oxygenic phototrophs by cyclic photophosphorylation involving only photosystem I. A、True B、False\n简答题\n Fermentations require an organic compound as the external electron acceptor for generating ATP. A、False B、True\n简答题\n _______ sulfate-reducing bacteria can also conserve energy from the reduction of elemental sulfur to sulfide. A、Some B、Very few C、None of D、Most\n简答题\n As __________, nitrate is reduced to nitrous oxide (N2O), nitric oxide (NO), and N2 in the process of denitrification. A、electron acceptors B、electron donors C、both electron donors and electron acceptors\n简答题\n _______ is a major electron donor in the processes of methanogenesis and acetogenesis. A、Methane B、CO2 C、Glucose D、H2\n简答题\n The acetogens and the methanogens are two major groups of strictly anaerobic prokaryotes use ____ as an electron acceptor for energy conservation. A、methane B、acetate C、H2 D、CO2\n简答题\n Fermentations do not require an external electron acceptor and they generate ATP as a result of substrate-level phosphorylation. A、False B、True\n简答题\n The reduced inorganic nitrogen compounds ammonia (NH3) and nitrite (NO2−) are oxidized _______ by the chemolithotrophic nitrifying bacteria in the process of nitrification. A、aerobically or anaerobically B、aerobically and then anaerobically C、aerobically D、anaerobically\n简答题\n Most chemolithotrophic bacteria are also autotrophs, which can growth on CO2 as the sole carbon source. A、True B、False\n简答题\n Under _______ conditions, ammonia is oxidized by a unique group of bacteria in the process called anammox. A、anoxic B、oxic C、oxic or anoxic D、both oxic and anoxic\n