In the version of the Ames test for potential human mutagenicity/carcinogenicity that I discussed in class, the chemicals are first mixed with an enzyme extract from rat liver before being tested on the bacteria. Why is the liver extract important? Question 2 Answer a. mammals have metabolic processes that could potentially turn a chemical considered not mutagenic into one that is or one that is considered mutagenic into one that is not cross out b. the liver extract helps to suppress 'background' nonsense mutations cross out c. the rat liver enzymes get rid of contaminating bacteria cross out d. the rat liver enzymes help to solubilize hydrophobic mutagens so they can get into the bacteria cross out e. liver enzymes are mutagenic on their own, so it acts as a control cross out f. the liver extract provides a key nutrient for the Salmonella bacteria to grow.