Male cockroaches with mutations that strongly decrease the function of an RTK (receptor tyrosine kinase) called RTKX are oblivious to the charms of their female comrades. This particular RTK binds to a small molecule secreted by sexually mature females. Most males carrying loss-of-function mutations in the gene for Ras protein are unable to respond to females. You have just read a paper in which the authors describe how they have screened cockroaches that are mutant in RTKX for additional mutations that partly restore the ability of males to respond to females. Propose two possible additional mutations in two separate genes from the receptor that could allow cockroaches with a mutant RTKX to now respond to females. You may consider mutations that could either increase or decrease the activity of the protein. Explain your answer.