Solved by a verified expert:Are there separate genes that determine the ability to taste the chemicals: phenylthiourea-phenylthiocarbamide (PTC paper), Thiourea, and sodium benzoate? For example, does an inherited gene allow one to taste all 3 of these chemicals or does gene “insert name” only allows the individual to taste one of the chemicals but not the other two, which may be determined by another gene. Are there 3 different genes that allow for the ability to taste the 3 different chemicals or perhaps one gene for that allows for the ability to taste PTC & Thiourea and not sodium benzoate, or maybe one that allows for the taste of sodium benzoate and PTC but not thiourea? How do inherited genes determine the taste of these 3 chemicals? (sorry for the long convoluted question).