A species of beetle expresses a pigment protein as an adult but not as a juvenile. The pigment is encoded by the gene PIG. A protein called KID, which is only present in juveniles, is a transcription factor that binds to the DNA near the protein-coding sequence for PIG. Do you think KID is a negative regulator of PIG or a positive regulator? Why?

Some individuals in the species never express the pigment (neither as a juvenile or as an adult). Do you think they have a mutation in the KID gene, the KID binding site, or in the protein-coding part of the PIG gene? Why? (the ‘why’ part of the question will only be used to help us give possible credit for answers different than what we think is the clearest answer)