In the ames test, the appearance of his+ revertants in the presence of a non-mutagenic control compound indicates that
a. there is some low-level contamination in most experiments
b. the growth medium contains factors that are mildly mutagenic
c. some of the reversion mutations are not caused by the mutagen being tested
d. liver extract increases the potency of some mutagens

i believe it would be the lungs.

i think its control and coordinate because im pretty sure thats what tissue does and the joints are what control movement and then your skeletal/ bones provides portection. hope that .

image result for how many calories of energy will 20 grams of carbohydrates provide in one gram provides 4 calories

consuming the right balance of protein, carbohydrates and fat can you maintain a healthy weight and optimize your energy levels. protein and carbohydrates both contain 4 calories per gram, while fat provides 9 calories per gram.