The experiment showed that energy production, or respiration, occurred in yeast even when little oxygen was present. During exercise, the lungs must work hard to take in oxygen, which then circulates to the body parts that need it. The ability to preform anaerobic respiration for short periods of time allows humans to sustain activity, even when oxygen is limited in the body.
What is anaerobic respiration ?
Anaerobic respiration is respiration using electron acceptors other than molecular oxygen (O2). Although oxygen is not the final electron acceptor, the process still uses a respiratory electron transport chain.
In aerobic organisms undergoing respiration, electrons are shuttled to an electron transport chain, and the final electron acceptor is oxygen. Molecular oxygen is an excellent electron acceptor. Anaerobes instead use less-oxidizing substances such as nitrate (NO−3), fumarate (C4H 2O2−4), sulfate (SO2−4), or elemental sulfur (S). These terminal electron acceptors have smaller reduction potentials than O2. Less energy per oxidized molecule is released. Therefore, anaerobic respiration is less efficient than aerobic.
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