Question

If necessary, our muscles can rely upon an anaerobic (fermentative) pathway to metabolize glucose, but this can only last a short period of time. Why can't our cells survive very long under such anaerobic conditions?

Answer 1

Fermentation can be used as an alternative method for metabolizing glucose and producing ATP but it cannot be used as a long-term method. This is because the method of fermentation produces very less ATP. The requirement of our body's cells for ATP is much more as compared to the ATP's generated by the method of fermentation.

By fermentation, a glucose molecule will generate only 2 ATP's. By aerobic respiration, 36-38 ATP's are generated.

Hence, our bodies cannot survive in anaerobic conditions for longer periods.