Why might we get negative result when testing a food item when we know the molecules we're testing for our present?

How do you transfer mrna into codons ? i'm so confused : (

What two fields of study provide the core information that is used to classify organisms?

What would most likely happen if a person increased the amount of saturated fat in his or her diet? the person's risk of cardiovascular disease would increase. the person's risk of cardiovascular disease would decrease. the person's bad cholesterol would decrease. the person’s good cholesterol would increase.