how do bivalves generate more ATP than humans during anaerob

how do bivalves generate more ATP than humans during anaerobic respiration?

Solution

The reason for this is:

In bivalves, the major end products produced during anaerobic respiration are generally succinate and alanine. These end products are not excreted from the body but upon return to aerobic respiration are reconverted to glycogen. Recovery from anoxia is rapid: tissue levels of alanine, aspartate, ATP are restored within 24 hrs.

Bivalves also have the ability to neutralise a portion of organic acids produced during anaerobic respiration by dissolving calcium carbonate from the shell. In humans on the other hand there is accumulation of lactic acid in the muscle cells. The waste product has potential energy that can be released by oxidation only