Definition: Arrhenotoky refers to the effect of heat on biological processes, particularly in relation to temperature sensitivity. It describes how molecular structures such as enzymes or proteins can change during high-temperature exposure. Definition: Arrhenotoky refers to the effect of heat on biological processes, especially in relation to temperature sensitivity. It's how molecular structures like enzymes or proteins can change during high-temperature exposure, often causing them to behave more randomly or spontaneously than they would under normal conditions.