Evolution
Components of the TCA cycle were derived from anaerobic bacteria, and the TCA cycle itself may have evolved more than once. Theoretically there are several alternatives to the TCA cycle, however the TCA cycle appears to be the most efficient. If several alternatives independently evolved, they all undoubtedly rapidly converged to the TCA cycle.
Read more about this topic: Citric Acid Cycle
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“The evolution of a highly destined society must be moral; it must run in the grooves of the celestial wheels.”
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