i dont really understand this very well may you please help me?
Respiration, cellular respiration can occur without oxygen. It is known as anaerobic respiration and uses respiratory electron transport chain. This chain performs its function through exogenous electron acceptor that allows the electron to pass through the system and must be present. In aerobic organisms oxygen is the final electron acceptor. In anaerobic organisms, Sulfate, Nitrate or Fumarate are used, these are relatively less efficient and have smaller reduction potential than O2; Oxygen indeed is highly oxidizing agent and releases lot of energy. Sulfate and Nitrate release less energy per oxidized molecule. Therefore, anaerobic respiration is relatively less efficient, occurs in prokaryotic organisms that live in environment without O2.
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