When you do rigorous exercise, the cells of the muscles require more oxygen. which condition ensures this requirement is met?

The correct answer is aerobic conditions.

When you do rigorous exercise, the cells of the muscles require more oxygen and this requirement is met through aerobic conditions.

The body has its own oxygen energy system that manages the presence of the oxygen during movement.

as the gila monster consumes the eggs or young of the desert cottontail and gambel's quail, thus its main food supply is only accessible for a restricted time duration every year. however, for this, the gila monsters exhibit three adaptations, which elevate their survival rate in the desert condition.  

first, is that they possess huge bodies, and can consume greater concentrations of food during a small period. secondly, they require to feed infrequently as they can accumulate fat in their tails. ultimately, their rate of metabolism is very low, so that they can burn their reservoirs of fat gradually.  

oxygen +1 most likely