The recycling of which compound ensures the continuation of glycolysis under anaerobic conditions?
fadh2
atp
nad+

The answer is NAD+.

In the process of glycolysis, NAD+ is reduced to form NADH+ and H+.  If NAD+ is not present, glycolysis will not be able to continue. Under anaerobic conditions, the regeneration of NAD is coupled to the reduction of pyruvate. The anaerobic regeneration of NAD is called fermentation.

In animal tissues , fermentation occurs as  pyruvate acts  as a makeshift hydrogen acceptor and gets  reduced to lactate when NADH transfers electrons to pyruvate. This enzyme catalyzed reaction occurs whenever the available oxygen has been consumed.

frogs. the lower the ph the higher the acid content. frogs have the highest tolerance in this scenario.