How do some cells become brain cells and others become skin cells, when the dna in all the cells is exactly the same. in other words, if the instructions are exactly the same, how does one cell become a brain cell and another a skin cell?

yes you are doing it right great gob

explanation:

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.